Concepts of Fitness And Wellness

78 Section 2  c  An Introduction to Physical Activity Pregnant women are nearly twice as likely as other by medical professionals, the American College of Sports women to be sedentary (fail to meet current activity guide- Medicine (ACSM) initiated a program called “Exercise Is lines) in spite of the fact that guidelines from the American Medicine (EIM)” designed to “encourage primary care phy- College of Obstetricians and Gynecologists indicate that sicians, and other health care providers, to assess and review most women should meet national guidelines as described. every patient’s physical activity program at every visit.” The More intense exercise is appropriate in many cases but initiative has taken off both in the United States and interna- should be done with “close medical supervision.” tionally. The website (www.exerciseismedicine.org) provides information to the general public, health-care providers, Physical activity can have positive effects on some health and fitness professionals, and the media. nonhypokinetic conditions. Physical activity helps to resolve symptoms and improve function and quality of life Physical activity is a major part of worksite and in people with the following conditions: school health promotion programs. Companies realize ∙ Arthritis. Many, if not most, people with arthritis are the importance of promoting healthy lifestyles among their employees. Worksite health promotion programs typically in a deconditioned state resulting from a lack of activ- focus broadly on promoting a variety of healthy lifestyles, ity. The traditional advice that those with arthritis should but physical activity is considered the mainstay of most pro- avoid physical activity is now being modified in view grams. To facilitate active lifestyles, many companies build of the findings that carefully prescribed exercise has a their own fitness centers inside the workplace or provide variety of benefits. Common problems for those with free or reduced-cost memberships for employees. Work- either rheumatoid arthritis or osteoarthritis are decreased site programs that promote activity can reduce risk factors strength, loss of range of motion, and poor cardiovascular in employees and help companies save money and control endurance. Well-planned exercise, designed to meet the the high cost of health care. Employees miss less work (i.e., needs of the specific type of arthritis of the individual, reduced absenteeism), are more productive while at work can be beneficial in preventing and treating impairments, (i.e., increased “presenteeism”), and have higher morale. and enhancing function, general fitness, and well-being. Schools, including many universities, also recognize the ∙ Asthma. People with asthma often have physical activ- importance of physical activity, resulting in the expansion ity limitations, but with proper management, activity can of fitness centers on many campuses. The expansion of be part of their daily lives. In fact, when done properly, worksite and school health physical activity programming activity can reduce airway reactivity and medication use. can provide benefits to individuals while also advancing Because exercise can trigger bronchial constriction, it is public health. important to choose appropriate types of activity and to use inhaled medications to prevent bronchial constriction Physical activity is an effective treatment for caused by exercise or other triggers, such as cold weather. rehabilitation of hypokinetic diseases and injury. People with asthma should avoid cold weather exercise. Physical activity is used to help people rehabilitate after a ∙ Premenstrual syndrome (PMS). PMS, a mixture of physi- heart attack, to cope with cancer treatments, and to recover cal and emotional symptoms that occur prior to menstru- from injuries (e.g., sports, accidents) and surgeries (e.g., ation, has many causes. However, changes in lifestyle, knee, hip, and shoulder replacements). including regular exercise, may be effective in relieving PMS symptoms. Many factors promote health and wellness and ∙ Cystic fibrosis. A recent review indicates that exercise helps reduce the risk for disease. Inactivity, poor nutrition, cystic fibrosis patients by facilitating systemic improve- smoking, and inability to cope with stress are all risk fac- ments and, more important, enhancing quality of life. tors associated with various chronic diseases. These factors ∙ Other conditions. Low- to moderate-intensity aerobic are in your control, and changing them can dramatically activity and resistance training are prescribed for some reduce your risk for chronic diseases. Other risk factors over people who have chronic pain (persistent pain without which you have some control include weight/body composi- relief) and/or fibromyalgia (chronic muscle pain). Evi- tion, blood lipids and other blood constituents, and blood dence also suggests that active people have a reduced pressure. You also have some control over your health care. chance of having gallstones, compared to inactive people. Recent reductions in chronic disease have resulted because Activity may also decrease the risk of impotence. of improved health care. For example, heart disease rates have decreased dramatically in recent years because of bet- Physical Activity as a Treatment ter detection (e.g., exercise tests, angiograms, CT scans), better emergency care, and improved medications. Physical activity is now recognized as effective “medicine” for prevention of chronic disease. Since Some risk factors, however, are not within your control physical activity is still not widely prescribed or promoted (e.g., age, heredity, and gender). Table 4 summarizes the risk factors that are within your control as well as those that are not. By adopting healthy lifestyles, you can take control

Concept 5  c  The Health Benefits of Physical Activity    79 Table 4  c  Hypokinetic Disease Risk Factors A CLOSER LOOK Factors That Cannot Be Altered 23 and ½ Hours! 1. Age.  As you grow older, your risk of contracting hypokinetic The benefits associated with regular physical activity are diseases increases. For example, the risk for heart disease is enormous, but participation in exercise and physical activ- approximately three times as great after 60 as before. The risk ity still remains low. A YouTube video by Dr. Mike Evans of back pain is considerably greater after 40. called “23 and ½ Hours” presents a compelling challenge to viewers: Commit 30 minutes a day to physical activity 2. Heredity.  People who have a family history of hypokinetic to ensure that you get the basic health benefits that come disease are more likely to develop a hypokinetic condi- from physical activity. (See link in Suggested Resources tion, such as heart disease, hypertension, back problems, and Readings.) obesity, high blood lipid levels, and other problems. African With so many powerful benefits of physical activity, why Americans are 45 percent more likely to have high blood do many people fail to put a high priority on it? pressure than Caucasians; therefore, they suffer strokes at an earlier age with more severe consequences. ACTIVITY 3. Gender.  Men have a higher incidence of many hypokinetic over some of the preventable disease risks. For example, by conditions than women. However, differences between men being physically active you can reduce your risk for heart and women have decreased recently. This is especially true disease and diabetes (even if you are overweight). Altering for heart disease, the leading cause of death for both men your diet can reduce the chances of developing high levels and women. Postmenopausal women have a higher heart of blood lipids and reduce the risk for atherosclerosis (even disease risk than premenopausal women. if you have a family history of the condition). Adopting healthy lifestyles is a proactive approach to health and well- Factors That Can Be Altered ness but it does not assure disease immunity. Even so, stud- ies of twins suggest that active people are less likely to die 4. Regular physical activity.  Regular exercise can help reduce early than inactive people with similar genes. This finding the risk for hypokinetic disease. suggests that long-term adherence to physical activity can overcome risk factors considered to be out of your control, 5. Diet.  A clear association exists between hypokinetic dis- such as heredity. Lab 5A helps you assess your heart dis- ease and certain types of diets. The excessive intake of ease risk factors, both those not in your control and those in saturated fats, such as animal fats, is linked to atheroscle- your control. Although the lab focuses on heart disease risk rosis and other forms of heart disease. Excessive salt in the factors, many of the factors are also risk factors for other diet is associated with high blood pressure. chronic diseases. Too much activity can lead to hyperkinetic conditions. 6. Stress.  People who are subject to excessive stress are pre- The information presented in this Concept points out the disposed to various hypokinetic diseases, including heart health benefits of physical activity performed in appropriate disease and back pain. Statistics indicate that hypokinetic amounts. When done in excess or incorrectly, physical activ- conditions are common among those in certain high-stress ity can result in hyperkinetic conditions, the most com- jobs and those having Type A personality profiles. mon being overuse injury to muscles, connective tissue, and bones. Recently, anorexia nervosa and body neurosis have 7. Tobacco use.  Smokers have five times the risk of heart been identified as conditions associated with inappropriate attack as nonsmokers. Most striking is the difference in risk amounts of physical activity. These conditions are discussed between older women smokers and nonsmokers. Tobacco in the Concept on performance. use is also associated with the increased risk for high blood pressure, cancer, and several other medical conditions. Hyperkinetic Conditions Diseases/illnesses or health condi- Apparently, the more you use, the greater the risk. Stopping tions caused, or contributed to, by too much physical activity. tobacco use even after many years can significantly reduce the hypokinetic disease risk. 8. Body (fatness).  Having too much body fat is a primary risk factor for heart disease and is a risk factor for other hypoki- netic conditions as well. For example, loss of fat can result in relief from symptoms of Type II diabetes, can reduce problems associated with certain types of back pain, and can reduce the risks of surgery. 9. Blood lipids, blood glucose, and blood pressure lev- els.  High scores on these factors are associated with health problems, such as heart disease and diabetes. Risk increases considerably when several of these measures are high. 10. Diseases.  People who have one hypokinetic disease are more likely to develop a second or even a third condition. For example, if you have diabetes,* your risk of having a heart attack or stroke increases dramatically. Although you may not be entirely able to alter the extent to which you develop certain diseases and conditions, reducing your risk and following your doctor’s advice can improve your odds significantly. *Some types of diabetes cannot be altered.

80 Section 2  c  An Introduction to Physical Activity Strategies for Action A self-assessment of risk factors adults often think “I’ll worry about these problems when I get can help you modify your lifestyle older.” But what you do early in life has much to do with your to reduce risk for heart disease. The Heart Disease Risk Fac- current health, as well as your health later in life. tor Questionnaire in Lab 5A will help you assess your personal risk factors for heart disease. It is not a substitute, however, for Subsequent Concepts in this book cover the different com- a regular medical exam that includes an assessment of other ponents of health-related fitness and the type and amount of cardiovascular disease risk factors, such as cholesterol and activity needed to improve these components. The lab activi- blood glucose. This will allow you to use more sophisticated ties in each of these Concepts are designed to help you begin and accurate risk factor assessments (see the Heart360.org planning now for lifelong physical activity. tool highlighted in the Technology Update feature). It is never too early to start being active to improve health. Many of the studies presented in this Concept indicate that being “active for a lifetime” prevents health problems. Young ACTIVITY Suggested Resources ∙ American Heart Association: Recommendations for Physical and Readings Activity in Adults. ∙ Centers for Disease Control and Prevention: Health and Academic Achievement (pdf). The websites for the following sources can be accessed by searching ∙∙ Harvard Nutrition Source: Simple Steps to Prevention of Diabetes. online for the organization, program, or title listed. Specific scientific Peterson, J. A. 2014. Need to know facts about diabetes. ACSM’s references are available at the end of this edition of Concepts of Fit- Health and Fitness Journal. 18(5): 56. ness and Wellness. ∙∙ USA Today: Diabetes Rates Fuel National Health Crisis. U.S. Department of Health and Human Services: U.S. Physical ∙ American College of Sports Medicine: Exercise Is Medicine Initiative. Activity Guidelines. ∙∙ American Heart Association: Heart360 Lifestyle Tracker. American Heart Association: My Life Check Heart Health ∙ YouTube Video by Mike Evans: “23 and 1/2 Hours.” Screener.

Lab 5A  Assessing Heart Disease Risk Factors Name Section Date Lab 5A Purpose: To assess your risk of developing coronary heart disease. See next page for directions. Heart Disease Risk Factor Questionnaire Risk Points 1 2 3 4 Score Assessing Heart Disease Risk Factors 30 or less 31–40 41–54 551  Unalterable Factors 1. How old are you? 2. Do you have a history of None Grandparent Parent with More than one with heart disease in your family? with heart heart disease heart disease disease 3. What is your gender? Female Male Total Unalterable Risk Score Alterable Factors 4–5 days 3 days Fewer than 3 No a week a week days a week 4. Do you get regular physical activity? 5. Do you have a high-fat diet? No Slightly high Above normal Eat a lot of meat and fried in fat in fat and fatty foods 6. Are you under Less than Normal Slightly above Quite high much stress? normal normal 7. Do you use tobacco? No Cigar or pipe Less than 1/2 More than 1/2 pack a day pack a day or use smokeless tobacco 8. What is your percentage F 5 17–28% 29–31% 32–35% .35% of body fat?* M 5 10–20% 21–23% 24–30% .30% 9. What is the systolic number ,120 121–140 141–160 .160 in your blood pressure? 10. Do you have other diseases? No Ulcer Diabetes** Both Extra Points: Add points for as many of the following test results as you have available: 1 point for CRP above 3, 1 point for homocyste- ine above 100, 3 points for LDL above 130, 3 points for TC/HDL-C above 4. If only total cholesterol is available, add 1 point for a score of 200–240 or 3 points for scores above 240. Total Alterable Risk Score Extra Points Grand Total Risk Score Adapted from CAD Risk Assessor, William J. Stone. Reprinted by permission. *If unknown, estimate your body fat percentage or see Lab 14A. **Diabetes is a risk factor that is often not alterable. 81

Lab 5A Procedures Assessing Heart Disease Risk Factors 1. Answer the 10 questions on the previous page and determine whether you should add the extra points on the Heart Disease Risk Factor Questionnaire by circling the answer that is most appropriate for you. 2. For each of your answers, look at the top of the column. In the box provided at the right of each question, write down the number of risk points for that answer. 3. Determine your unalterable risk score by adding the risk points for questions 1, 2, and 3. 4. Determine your alterable risk score by adding the risk points for questions 4 through 10. 5. Determine your total heart disease risk score by adding the scores obtained in steps 3 and 4. 6. Look up your risk ratings on the Heart Disease Risk Rating Chart and record them in the Results section. Answer the questions in the Conclusions and Implications section. Results: Write your risk scores and risk ratings in the appropriate boxes below. Heart Disease Risk Scores and Ratings Score Rating Unalterable risk Alterable risk Total heart disease risk Heart Disease Risk Rating Chart Rating Unalterable Score Alterable Score Total Score Very high 9 or more 21 or more 31 or more High 7–8 15–20 26–30 Average 5–6 11–14 16–25 Low 4 or less 10 or less 15 or less Conclusions and Implications: The higher your score on the Heart Disease Risk Factor Questionnaire, the greater your heart disease risk. In several sentences, discuss your risk for heart disease. Which of the risk factors do you need to control to reduce your risk for heart disease? Why? 82

How Much Physical Concept 6 Activity Is Enough? LEARNING OBJECTIVES After completing the study of this Concept, you will be able to: c Describe each of the key principles of physical activity and explain how the principles relate to each other in helping you achieve health, wellness, and fitness. c Name the four elements of the FITT formula and explain how the formula relates to the concepts of threshold of training and target zones for different types of physical activity. c List the five steps in the physical activity pyramid and identify the FIT formula for each. c Describe the physical activity patterns of adults, differentiating among groups based on age, gender, and ethnicity. c Describe the four fitness zones used for self- assessments of physical fitness and explain how each level relates to health and performance. c Identify related national health goals and show how meeting personal goals can contribute to reaching national goals. c Self-assess your current activity level for each step of the physical activity pyramid and estimate your current health and skill-related physical fitness. There is a minimal and an optimal amount of physical activity necessary for developing and maintaining good health, wellness, and fitness. 83 83

84 Section 2  c  An Introduction to Physical Activity goal is to improve performance in putting the shot, it is not enough to strengthen the arm muscles. You should train Physical activity is a behavior that contributes to health, using exercises that require overload of all muscles used and wellness and fitness. However, for physical activity to that require motions similar to those used in putting the shot. have an optimal effect, the appropriate amount of activity must The benefits achieved from overload last only as long be performed. This Concept describes the basic principles of as overload continues. The principle of reversibility is physical activity, including the FITT formula, and key con- the overload principle in reverse. To put it simply, if you cepts such as threshold of training and target zones. Use the don’t use it, you lose it. Some people have the mistaken physical activity pyramid to help understand and remember impression that if they achieve a health or fitness benefit physical activity guidelines for different types of activities. it will last forever. Although there is evidence that you can maintain health benefits with less physical activity than it The Principles of took to achieve them, if you do not engage in regular physi- Physical Activity cal activity, any benefits attained will gradually erode. In general, the more physical activity you do, the Overload is necessary to achieve the health, more benefits you receive. Just as there is a correct dosage of medicine for treatment of illness, there is a cor- wellness, and fitness benefits of physical activity. rect dosage of physical activity for promoting health ben- The overload principle, the most basic of all physical efits and the development of physical fitness. Though there activity principles, indicates that doing “more than normal” are some exceptions, a considerable amount of research is necessary if benefits are to occur. In order for a muscle indicates that benefits from physical activity follow a (including the heart muscle) to get stronger, it must be dose-response relationship—the more physical activity overloaded, or worked against a load you perform, the more benefits you gain. greater than normal. To increase flex- ibility, a muscle must be stretched Figure 1 illustrates the overall pattern of the dose- longer than is normal. To increase VIDEO 1 response relationship. The red bar indicates the high risk for hypokinetic disease and early death for those who are muscular endurance, muscles must inactive. A modest increase in physical activity, such as the be exposed to sustained exercise for a longer than normal 30 minutes of moderate activity recommended in the physi- period. The health benefits associated with metabolic fit- cal activity guidelines, results in a substantial decrease in ness seem to require less overload than for health-related risk and early death (green bar). Additional activity (blue fitness improvement, but overload is required, just the same. bar) has extra benefits, but the benefits are not as great as those that come from making the change from being inactive Increase physical activity progressively for safe and to doing some activity. As the black bar indicates, very high effective results. The principle of progression indicates levels of activity produce little additional health benefit. that overload should occur in a gradual progression rather than in major bursts. Failure to adhere to this principle can The “dose” of activity necessary to get one benefit is not result in excess soreness or injury. Although some tightness the same as the “dose” for another. For example, changes or fatigue is common after exercise, it is not necessary to feel in cholesterol levels resulting from physical activity may sore in order to improve. Training is most effective when the change at a different rate than changes in blood pressure. sessions become progressively more challenging over time. Many benefits in health, wellness, and fitness are obtained with moderate amounts of activity, so the key is to be at least The benefits of physical activity are specific to the active enough to obtain these benefits. form of activity performed. The principle of specificity states that to benefit from physical activity you must overload High Risk Inactive specifically for that benefit. For example, strength-building exercises may do little for developing cardiorespiratory fit- Moderate Moderately Very Big drop ness, and stretching exercises may do little for altering body Risk Active Active in risk composition or metabolic fitness. More Less drop Active in risk Overload is also specific to each body part. If you exer- Even less cise the legs, you build fitness of the legs. If you exercise drop in risk the arms, you build fitness of the arms. Some gymnasts, for example, have good upper body development but poor Low Risk leg development, whereas some soccer players have well- developed legs but lack upper body development. Figure 1  c  Decreases in hypokinetic disease risk with increases in dose of activity Specificity is important in designing your warm-up, workout, and cool-down programs for specific activities. Training is most effective when it closely resembles the activity for which you are preparing. For example, if your

Concept 6  c  How Much Physical Activity Is Enough?    85 In the News Employer Fitness Programming Through the Affordable Care Act The Affordable Care Act (ACA) includes key incorporated into policies and programs. (See link in Suggested incentives that encourage employers to offer Resources and Readings.) wellness programs to their employees. Examples of supported Would you take advantage of employer-sponsored fitness programming include reimbursement for fitness center mem- programming if available? Should employers offer incentives berships and rewards to employees for attending seminars to employees who are active and fit? or for completing health risk appraisals. The degree of imple- mentation varies by state and by how various components are ACTIVITY The rate of improvement levels off as you become The FITT Formula more fit, and at some point maintenance is an appropriate goal. The principle of diminished returns The acronyms FITT and FIT help you remember explains the rate and degree of impovement decrease as important variables for applying the overload principle. a person gets more fit. Beginners (people in the low and For physical activity to be effective, each type of activity marginal fitness zones) often see relatively large fitness must be done with enough frequency, with enough intensity, improvements when they begin an exercise program. How- and for a long enough time. The first letters from four words ever, people with higher levels of fitness must do consid- spell FITT and can be considered as the formula for achiev- erably more activity to continue to improve. For example, ing health, wellness, and fitness benefits. a person who runs a mile in 15 minutes may cut several minutes from his or her running time in the first month or Frequency (how often)—Physical activity must be performed two of training. A fitter person who currently runs a mile in regularly to be effective. Most benefits require 3 to 5 days 5 minutes would have to do considerably more training to of activity per week, but frequency ultimately depends on cut his or her time by even a few seconds. For most people, the specific activity and the benefit desired. reaching the good fitness zone is a worthwhile goal. As the principle of diminishing returns indicates, those interested Overload Principle You must perform physical activity in in high-level competition requiring high levels of fitness greater than normal amounts (overload) to improve physical fit- will have to follow high volume exercise regimens. ness or obtain health benefits. Principle of Progression  You need to gradually increase over- Rest is needed to allow the body to adapt to exercise. load to achieve optimal benefits. The principle of rest and recovery indicates that you Principle of Reversibility  Disuse or inactivity results in loss of should allow time for recuperation after overload. Proper benefits achieved as a result of overload. rest is needed within intense periods of activity, and appro- Principle of Specificity  Specific types of exercise are needed to priate rest is needed between training sessions. Rest pro- improve each fitness component or the fitness of a specific part vides time for the body to adapt to the stimulus provided of the body. during the workout. Failure to take sufficient rest can lead Dose-Response Relationship A term adopted from medicine. to overuse injuries, fatigue, and reduced performance. For With medicine, it is important to know what response (benefit) will recreational exercisers, rest generally implies taking a day occur from taking a specific dose. When studying physical activity, off between bouts of exercise or alternating hard and easy it is important to know what dose provides the best response (most days of exercise. benefits). Principle of Diminished Returns  The more benefits you gain All people benefit from physical activity, but the as a result of activity, the harder additional benefits are to achieve. benefits are unique for each person. Heredity, age, Principle of Rest and Recovery You need adequate rest to gender, ethnicity, lifestyles, current fitness and health allow the body to adapt to and recover from exercise. status, and a variety of other factors make each person Principle of Individuality  Overload provides unique benefits to unique at any point in time. The principle of individuality each individual based on the unique characteristics of that person. indicates that the benefits of physical activity vary from FITT, FIT A formula used to describe the frequency, intensity, individual to individual based on each person’s unique time, and type of physical activity necessary to produce benefits. characteristics. When the type of activity has been determined, the second T is dropped and the shorter acronym FIT is used.

86 Section 2  c  An Introduction to Physical Activity Intensity (how hard)—Physical activity must be intense High Too much enough to require more exertion (overload) than normal to produce benefits. The appropriate intensity varies with Amount Target zone Optimal the desired benefit. Health benefits from metabolic fit- of Threshold of training level ness require only moderate activity, but performance Not benefits require more vigorous activity. activity “Normal activity” enough Time (how long)—Physical activity must be done for an adequate length of time to be effective. The length of the Low Inactivity activity session depends on the type of activity and the Figure 2  c  Physical activity target zone. expected benefit. typically on a weekend day. Concepts that follow discuss Type (kind of activity)—The benefits derived depend on various patterns of exercise and show how they can be used the type of activity performed. For example, moderate to accumulate the desired daily volume of exercise. activity must be done at least 5 days a week, while mus- cle fitness activity may be done as few as 2 days a week. Threshold of training and target zone help you use the FIT formula. The threshold of training is the mini- When determining the formula for each type of activity, the shorter acronym (FIT) can be used because you have already determined the activity type. In the following sec- tion, you will learn more about the FIT formula for each activity in the physical activity pyramid. In subsequent Concepts, each formula is described in greater detail. The volume and progression of physical activity are mum amount of activity (frequency, intensity, and time) necessary to produce benefits. Depending on the benefit important considerations. The American College of expected, slightly more than normal Sports Medicine (ACSM) uses the acronym FITT-VP to illustrate the importance of volume activity may not be enough to promote health, wellness, or fitness benefits. and progression in planning your The target zone begins at the thresh- VIDEO 3 exercise program. Volume refers to the total amount of physical activity that VIDEO 2 old of training and stops at the point you perform each day. It is a combi- where the activity becomes counterproductive. Figure 2 illustrates the threshold of training and target zone concepts. nation of the frequency, intensity, and total amount of time Some people incorrectly associate threshold of training spent in exercise. For example, a short but more intense bout of activity can provide a volume of activity similar and target zones with only cardiorespiratory fitness. As the principle of specificity suggests, each component of fitness, to a longer, moderate exercise bout. Various combinations including metabolic fitness, has its own FIT formula and its of frequency, intensity, and time of physical activity (vol- ume) can be used in a gradual progression to reach personal own threshold and target zone. The target and threshold lev- els for health benefits are different from those for achieving goals based on individual needs. Progression, in this con- performance benefits associated with high levels of physi- text, refers to the application of the principle of progression described earlier in this Concept. Essentially, to continue to cal fitness. improve you have to progress (i.e., increase) any or all of the FIT components. However, being patient is important, too. Attempts to get fit fast will probably be counterproductive, The Physical Activity Pyramid so the key is to start slowly and progress gradually using the The physical activity pyramid classifies activities by FITT formula. type and associated benefits. The physical activity pyra- mid (see Figure 3) was created to help readers better under- Various patterns of physical activity can be used to stand the five basic types of physical activity (e.g., the last T achieve the recommended volume. The recommended in FITT). Over the years, it has proven volume of exercise for achieving health benefits can be to be a useful model for illustrating how accumulated in several short bouts (10 minutes or longer) or each type of activity contributes to the in one longer bout to reach a daily total of 30 minutes. Other development of health, wellness, and VIDEO 4 patterns of exercise include intermittent versus continuous exercise and different patterns of exercise for muscle fitness fitness. The pyramid depicts five differ- (e.g., periodization). The ACSM discourages the “week- ent steps. Each step represents a step toward achieving health, end warrior” pattern that includes no regular exercise but wellness, and fitness. Inactivity is shown below the pyramid “a large total volume” of exercise on one day of the week, because it does not represent a step toward active living. Place- ment in the pyramid is not meant to suggest that higher steps

Concept 6  c  How Much Physical Activity Is Enough?    87 Energy Balance Energy Out Energy In (Activity) (Diet) STEP 5 F 5 31 days/wk Flexibility • Yoga I 5 Stretch overload Exercises • Stretch T 5 10–30 sec, • Calisthenics 2–4 reps per • Resistance muscle group exercise STEP 4 • Tennis • Hike F 5 2–3 days/wk Muscle I 5 Muscle overload Fitness • Jog T 5 8–12 reps, 2–4 sets Exercises • Bike • Aerobic dance per muscle group • Walk STEP 3 Vigorous Sports • Yard work and Recreation • Golf F 5 31 days/wk I 5 Noticeably increased heart rate T 5 201 minutes/day* STEP 2 Vigorous Aerobics F 5 31 days/wk I 5 Noticeably increased heart rate T 5 201minutes/day* STEP 1 Moderate Physical Activity F 5 51 days/wk I 5 Equal to brisk walking T 5 301minutes /day* *150 minutes of moderate or 75 minutes of vigorous activity per week is recommended; moderate and vigorous activity can be combined to meet guidelines. Avoid Inactivity Figure 3  c  The physical activity pyramid. Source: C. B. Corbin. are more important than lower steps. Activities from all steps Each of the five steps of the physical activity pyramid are are important for optimal health, wellness, and fitness. Key discussed in greater detail in the paragraphs that follow as concepts illustrated by the physical activity pyramid include well as in later Concepts. the following: Threshold of Training  The minimum amount of physical activ- ∙ Each type of activity has its own FIT formula and unique ity that will produce health and fitness benefits. health, wellness, and fitness benefits. Target Zone  The amounts of physical activity that produce opti- mal health and fitness benefits. ∙ The different types of physical activity can be combined Health Benefits The results of physical activity that provide to meet activity guidelines. protection from hypokinetic disease or early death. Performance Benefits The results of physical activity that ∙ Extended periods of inactivity can be harmful to your improve physical fitness and physical performance capabilities. health. ∙ Eating well (sound nutrition) is an important companion behavior to physical activity (see energy balance scale at the top of Figure 3).

88 Section 2  c  An Introduction to Physical Activity Vigorous sports can actively commute (bike or walk) to work or to run errands provide health and have also been found to have better health profiles. The reg- wellness benefits. ular accumulation of activity as a part of one’s lifestyle is sufficient to promote positive improvements in metabolic fit- Inactivity can be ness, and these improvements can positively impact health. hazardous to your Additional activity from the other layers of the pyramid are health. The steps strongly recommended. Moderate activity can be viewed as the baseline, or minimal, activity that should be performed. in the physical A summary of the FIT formula for moderate activity is illus- activity pyra- trated in step 1 of Figure 3. mid show the five differ- Vigorous aerobic activity provides additional health ent types of benefits. Vigorous aerobic activities (step 2) are of greater physical activ- intensity than moderate activities (step 1). The greater inten- ity (Figure 3). sity results in significantly higher heart rates and higher oxy- The words gen consumption. Because of its greater intensity, vigorous aerobics can be performed as few as 3 days a week and is “Avoid Inactivity” especially good for building cardiorespiratory fitness and appear below the helping to control body fatness. Examples of vigorous aero- pyramid in bold black letters. bic activities, sometimes referred to as active aerobics, are This is important because current evidence jogging, biking, and aerobic dance. Vigorous aerobic activi- indicates that people who are inactive for large portions of ties can provide metabolic fitness and health benefits similar the day have an increased risk of chronic disease. Even active to moderate activities and can be performed instead of, or people are at risk if they are sedentary for long periods of in combination with, moderate activities to meet national time when not involved in activity. See the Concept on mod- activity guidelines. erate physical activity, for additional information. Moderate activities provide many benefits for modest Vigorous sports and recreation activities can amounts of effort. Moderate aerobic activities equal in provide similar benefits as vigorous aerobic activity. intensity to brisk walking provide significant health benefits. Vigorous sports and recreation are activities of similar For a variety of reasons, they are depicted as step 1 of the intensity to vigorous aerobics. Some sports, such as golf physical activity pyramid (see Figure 3). The broad bottom of and bowling, can be classified as moderate aerobic activities the pyramid illustrates that moderate activities are the most because they are of a lower intensity. Vigorous sports and widely performed activities among adults. For optimal ben- recreation activities (see Figure 3, step 3) can be performed efits, moderate activities are performed 5 or more days per instead of, or in combination with, vigorous aerobic activities week compared to 2 to 3 days per week for activities in steps or moderate activities, to meet national activity guidelines. 2 to 5. Finally, and perhaps most important, moderate activi- ties provide many benefits for a modest amount of effort Muscle fitness exercises are important for optimal (see Figure 1). Moderate aerobic activities, such as walking fitness and health. There are muscle fitness benefits from to and from work, climbing the stairs rather than taking an many different activities, including vocational activities elevator, or doing brisk housework when done as part of the that require lifting, active sports such as gymnastics and normal daily routine are often referred to as lifestyle physical wrestling, and recreational activities such as rock climb- activities. Moderate activities that are not part of the normal ing. Various muscle fitness activities, such as resistance daily routine, such as taking a walk or a bike ride, can also be training and calisthenics, are included at step 4 of the pyra­ planned specifically to increase activity levels. mid and they contribute to strength, muscular endurance, Studies indicate that individuals with active jobs have and power. The many health and performance benefits of reduced risks for many chronic conditions. Those who muscle fitness exercises are described in the Concept on muscle fitness. A general description of the FIT formula for muscle fitness exercises is included in Figure 3 (step 4). Flexibility exercises are important for building and maintaining flexibility. There are flexibility benefits from many different activities, including sports such as gymnas- tics and diving. The flexibility exercises included at step 5 of the pyramid are those that are planned specifically to build flexibility, such as stretching exercises and yoga. The many

Concept 6  c  How Much Physical Activity Is Enough?    89 TECHNOLOGY UPDATE ∙ Something is better than nothing. Some people may say, “I just don’t have time to do all of the activities in the Activity Monitors pyramid.” This could lead some to throw up their hands in despair, concluding, “I just won’t do anything at all.” The consumer marketplace is flooded with a variety of Evidence indicates that something is better than nothing, physical activity monitors designed to help people track so try to do a little activity and add more as time allows. their exercise behaviors (e.g., Fitbit, Jawbone UP). Most link wirelessly with associated smartphone apps so that ∙ Activities from steps 2 and 3 can be used instead of, or in users can get real-time reports of their physical activ- combination with, those from step 1 to achieve health and ity behaviors. The monitors capture movement with fitness benefits. While more people typically perform small accelerometers and combine these data with other moderate activities (step 1), many prefer more vigorous sensors to estimate activity and energy expenditures. activities from steps 2 and 3 of the pyramid. Both pro- Research has shown that although most devices provide vide health benefits and the two can be combined to meet reasonable estimates for consumer applications, accuracy activity guidelines. doesn’t rank high as a consumer concern. (See link in Sug- gested Resources and Readings.) ∙ Activities from steps 4 and 5 are useful even if you are limited in performing activities at other levels. It is best What features are most important to you when choosing to include some activities from steps 1, 2, and 3, but mus- an activity monitor? cular exercise and flexibility exercise do provide benefits on their own. ACTIVITY ∙ Good planning will allow you to schedule activities from benefits of flexibility exercises are described in the Concept all steps in a reasonable amount of on flexibility. A general description of the FIT formula for time. In subsequent Concepts, you VIDEO 5 flexibility exercises is included in Figure 3 (step 5). will learn more about each step of the pyramid, as well as how to plan Energy balance is important for maintaining a healthy a total physical activity program. body composition. Weight management requires that energy intake be matched by energy expenditure. The FIT ∙ Specific activity recommendations exist for youth. formula messages in the physical activity pyramid provide According to guidelines, children should accumulate general information about the amounts of activity (energy at least 60 minutes, and up to several hours, of age- expenditure) necessary for general health and fitness ben- appropriate physical activity on most, if not all, days of efits. But these amounts may not be enough for weight the week. The guidelines also recommend minimizing management (or weight loss). Current physical activity periods of inactivity (periods of 2 or more hours). Adults guidelines suggest that 45 to 60 minutes of daily moderate play a major role in shaping children’s current and future activity may be necessary (as opposed to 30 minutes). activity patterns. The balance scale at the top of the pyramid in Figure 3 ∙ Specific guidelines exist for older adults. Specific activ- illustrates the importance of balancing energy intake with ity guidelines are available for adults 65 and older. The energy expenditure. More information about maintaining guidelines are similar to those for younger adults but dif- energy balance for body composition is included in the Con- fer in some important ways. The guidelines for intensity cepts on nutrition and diet. of aerobic activity take into account the older adult’s activity level. Also, older adults typically do more repeti- Some important factors should be considered when tions and use less resistance when doing muscle fitness using the physical activity pyramid. The physical activ- exercise, flexibility exercises become more important, ity pyramid is a useful model for describing different types and exercise for balance is recommended. of activity, their benefits, and the FIT formula for each level. However, it shouldn’t be interpreted too rigidly. The follow- Moderate Aerobic Activities  Aerobic activities equal in inten- ing statements summarize the key points: sity to a brisk walk are referred to as moderate activities (see step ∙ No single activity provides all of the benefits. Many peo- 1 of the activity pyramid). Vigorous Aerobic Activities Vigorous aerobic activities that ple wonder “What is the perfect form of physical activ- elevate the heart rate and are greater in intensity than a brisk walk ity?” There is no single activity that can provide all of the (see step 2 of the activity pyramid). health, wellness, and fitness benefits. It is best to perform Vigorous Sports and Recreation Sports such as soccer and activities from all steps of the pyramid because each type volleyball, or recreational activities such as hiking, that elevate of activity has different benefits. the heart rate and are of greater intensity than a brisk walk. (See step 3 of the physical activity pyramid.)

90 Section 2  c  An Introduction to Physical Activity Physical Activity Patterns more likely to be totally inactive than college graduates and meet national activity goals less frequently. Adults with one The percentage of adults who meet national health or more physical disabilities have a high probability of being goals varies by gender, age, and ethnicity. National inactive. Minority groups have high rates of inactivity, and as physical activity goals have been established for moderate illustrated in Table 1, White non-Hispanics are more likely to to vigorous aerobic physical activity as well as for muscle fitness exercise. As noted in Table 1, only about half of Table 1  c  Percentages of Adults Who Meet Americans meet national goals for aerobic activity and less National Activity Goals than one-quarter of adults meet both aerobic activity and muscle fitness goals. For both types of activity, men are Classification Aerobic Activity Both Aerobic and more active than women, young adults are more active than Muscle Fitness older adults, and non-Hispanic Whites are more active than Activity non-Hispanic Blacks and Hispanics. The good news is that the numbers in Table 1 show higher percentages of adults Gender Percent Percent meeting activity goals than in the past: 49 percent of adults meet the national goal for aerobic activity, up from 43 per-  Male 53 26 cent 10 years earlier. The not-so-good news is that 50 percent of adults do not perform the minimum amount of activity  Female 45 17 necessary for gaining the health and fitness benefits of aero- bic exercise. Fewer adults meet guidelines for muscle fitness  Combined 49 22 exercise than for moderate or vigorous aerobic activity. Age Percent Percent The proportion of people meeting national health goals varies based on age. Children are the most active group  18–24 60 31 in Western society. During adolescence, activity starts to decrease, but teens still do more activity than young adults.  25–64 50 22 Activity levels of all types decrease from young adulthood to ages 65 and over (see Table 1).  65–74 37 15 The proportion of adults meeting national health goals  751  25  8 varies based on income, education, and disability status. People at or near poverty levels are more than twice as Ethnicity Percent Percent likely to be totally inactive during leisure time, compared with those with high income. Low-income people are also much less   Non-Hispanic White 51 23 likely to meet national health goals for activity than middle- to high-income people. High school dropouts are three times   Non-Hispanic Black 46 23  Hispanic 43 15 Source: National Health Interview Survey. A CLOSER LOOK The Tabata Workout Tabata promotes the concept of a “4-minute workout” as if it is equivalent in benefits to longer regimens. Although interval Fitness enthusiasts are often confronted with advertisements for training and cross training are effective methods, be careful enhanced workout methods that claim to offer new advantages, and cautious about new claims. Search “Tabata” online to learn including the recent hype around “Tabata” workouts. This regi- more. (See link in the Suggested Resources and Readings.) men is built on a popular, fairly recent training modality called high-intensity interval training (or HIIT). Both HIIT and Tabata are Would you consider this type of regimen in order to maximize really just new versions of an established training method called the intensity of your workout, or would this approach detract interval training that involves alternating bouts of high-intensity from your enjoyment of a normal workout? exercise with periods of rest. The goal is to increase the intensity of the overall workout and provide a greater stimulus. However, ACTIVITY

Concept 6  c  How Much Physical Activity Is Enough?    91 HELP Health is available to Everyone Table 2  c  The Four Fitness Zones for a Lifetime, and it’s Personal The U.S. Physical Activity Guidelines from the Centers for High-Performance Zone Disease Control and Prevention (CDC) indicate that adults Reaching this zone provides additional health benefits should get a minimum of 150 minutes of moderate activity and is important to high-level performance. However, high each week (e.g., 30 minutes five days a week). However, performance scores are hard for some people to achieve, performing 75 minutes of vigorous activity per week also and for many people high-level performance is not important. meets the guidelines. The flexible guidelines provide dif- So reaching this zone may be more important to some than ferent ways to be physically active. (See link in Suggested others. Resources and Readings.) Good Fitness Zone Based on your interests, would you lean toward the If you reach the good fitness zone, you have enough of moderate or the vigorous guideline—or a combination a specific fitness component to help reduce health risk. of both? However, staying active (in addition to reaching this fitness zone) is important. ACTIVITY Marginal Zone meet national activity goals than Hispanic and non-Hispanic Marginal scores indicate that some improvement is in order, Blacks. While no information was provided in the most recent but you are nearing minimal health standards set by experts. survey for Asian Americans, previous surveys indicate that they are similar in activity levels to White non-Hispanics. Low-Fit Zone If you score low in fitness, you are probably less fit than you should be for your own good health and wellness. Physical Fitness Standards in the low fitness zone have a higher risk than those in the other three zones and a goal should be to first strive to VIDEO 7 Health-based criterion-referenced standards are move out of the low zone into the mar- recommended for rating your fitness. This Concept has focused on the amount of physical activity necessary to get ginal zone. Those in the marginal zone are at lower risk than those in the low fitness zone, but they should strive to move health and fitness benefits. Another question to be answered into the good fitness zone. is “How much physical fitness is enough?” Most experts recommend health-based criterion-referenced standards With reasonable amounts of physical activity over time, most people should be able to improve their fitness to rate your current fitness. These standards are based on enough to make it into this range. For personal reasons, how much fitness is needed for good health. Other standards use norms or some may wish to aim for the high performance zone. Attaining this level may provide some additional health percentiles that compare a person’s benefits, but the effort required is great. Reaching the high fitness against a reference population. VIDEO 6 performance zone will be important for those interested in Knowing how you compare with other high-level performance but should not be a goal of those people is not that important. In fact, such comparisons have been shown to be discouraging to many people. Determin- in the low fitness or marginal zones until the good fitness zone is reached. ing if your fitness is adequate to enhance your health and wellness is more relevant. In the Concepts that follow, you will perform many differ- ent self-assessments to determine your fitness zone for each dimension of fitness. Four different rating zones are used Health-Based Criterion-Referenced Standards  The amount (see Table 2). The long-term goal is to achieve the “good fit- of a specific type of fitness necessary to gain a health or wellness ness zone,” a standard associated with good health. People benefit.

92 Section 2  c  An Introduction to Physical Activity Strategies for Action A self-assessment of your current self-assessments of fitness and will learn the scores that are activity at each level of the pyramid necessary on these assessments to reach the good fitness can help you determine future activity goals. Lab 6A provides zone, as described in Table 2. In the meantime, you can com- you with the opportunity to assess your physical activity at each plete Lab 6B. This lab will help you understand the nature of level of the pyramid. each part of fitness and estimate your current fitness level for each type of fitness. When you complete the more detailed self- Self-assessments of physical fitness can help you prepare a assessments later in the book, you will be able to determine the fitness profile that can be used in program planning. In the accuracy of your estimates. Concepts that follow, you will learn to perform a variety of ACTIVITY Suggested Resources ∙ Centers for Disease Control and Prevention: Facts About Physical and Readings Activity. The websites for the following sources can be accessed by searching ∙ Centers for Disease Control and Prevention: National Health online for the organization, program, or title listed. Specific scien- Interview Survey 2014. tific references are available at the end of this edition of Concepts of Fitness and Wellness. ∙ Centers for Disease Control and Prevention: Promoting Prevention Through the Affordable Care Act. ∙ ACSM. (2014). ACSM’s Guidelines for Exercise Testing and ∙ Lavie, C. J. et al. (2015). Exercise and the heart—the harm of Prescription, 9th ed. Philadelphia: Lippincott, Williams & too little and too much. Current Sports Medicine Reports, 14(2): Wilkins. 104–109. ∙ Olson, M. (2014). TABATA: It’s a HIIT! ACSM’s Health & ∙ Briner, W. W. (2014). How much is too much? When not to Fitness Journal, 18(5), 17–24. push through exercise. ACSM’s Health and Fitness Journal, ∙ Roy, B. A. (2015). Overreaching/overtraining: More is not always 18(6): 39–40. better. ACSM’s Health and Fitness Journal. 19(2): 4–5. ∙∙ Science Daily: Report on Accuracy of Fitness Bands. ∙ Bushman, B. A. (2014). Determining the I (intensity) for a U.S. Health and Human Services: U.S. Physical Activity Guidelines. FITT-VP aerobic exercise prescription. ACSM’s Health and Fitness Journal, 18(3): 4–7.

Lab 6A  Self-Assessment of Physical Activity Name Section Date Lab 6A Purpose: To estimate your current levels of physical activity from each category of the physical activity pyramid. Procedures Self-Assessment of Physical Activity 1. Place an X over the circle that characterizes your participation in each category in the pyramid. Place an X over one circle, at the bottom of the pyramid, to indicate days of inactivity. 2. Determine if you met the national goal for each type of activity. In the Results section of the chart on the next page, place an X over the “yes” circle if you meet the goal in each area or an X over the “no” circle if you do not meet the goal. Energy Balance Energy Out Energy In (Activity) (Diet) In the last week, how many days did STEP 5 you do stretching exercises for flexibility? 01 234567 In the last week, how many days STEP 4 did you do muscle fitness exercises for strength or muscular endurance? 01 234567 STEP 3 In the last week, how many days did you perform 20+ minutes of vigorous sports or recreation? STEP 2 01 234567 In the last week, how many days did you perform 20+ minutes of vigorous aerobics? 01 234567 STEP 1 In the last week, how many days did you perform 30+ minutes of moderate activity? 01 234567 Inactivity In the last week, how many days did you fail to do any activities from the 5 steps above? 01 234567 93

Lab 6A Results Step National Goal Did You Meet the National Health Goal? 1 5 days or more Yes            No Activity Type Yes            No Moderate activity 2 and 3 3 days or more Yes            No Vigorous activity Yes            No Muscle fitness 4 2 days or more Yes            No Flexibility exercises Inactivity 5 3 days or more Self-Assessment of Physical Activity — Avoid total inactivity Conclusions and Implications: In the space below, describe your current physical activity patterns. Do you meet the national health goals in all areas? If not, in what types of activity from the pyramid do you need to improve? Are the answers you gave for the past week typical of your regular activity patterns? If you meet all national health goals, explain why you think this is so. Do you think that meeting the goals in the pyramid on the previous page indicates good activity patterns for you? 94

Lab 6B  Estimating Your Fitness Name Section Date Lab 6B Purpose: To help you better understand each of the 11 dimensions of health-related and skill-related physical fitness. Procedures Estimating Your Fitness 1. Consider a warm-up before and cool-down after. Perform each of the activities described in Chart 1 on the next page. 2. Estimate your current fitness levels. Place a checkmark in the appropriate circle for each fitness dimension in the Results section below. If the activity was difficult or if past tests suggest it, check the “low fitness” circle; if the activity was somewhat difficult or if you think you need improvement, check the “marginal fitness” circle; if the task was rela- tively easy or if past tests indicate it, check the “good fitness” circle; and if you think your fitness in an area is sufficient, check the “high performance” circle. Special Note: The activities performed in this lab are not intended as valid tests of physical fitness. Completing the activities will help you better understand each dimension of fitness. You should not rely primarily on the results of the activities to make your estimates. Consider previous fitness tests you have taken and your own best judgment of your cur- rent fitness. In later Concepts, you will learn how to perform accurate assessments of each fitness dimension that will help you to assess the accuracy of your estimates. Results Fitness Zones Low Marginal Good High Fitness Fitness Fitness Component Fitness Performance Body Composition Cardiorespiratory Endurance Flexibility Muscular Endurance Power Strength Agility Balance Coordination Reaction Time Speed Conclusions and Implications: Describe the information you used to make your estimates of physical fitness. How confident are you that these estimates are accurate? 95

Directions: Attempt each of the activities in Chart 1. Place a checkmark in the circle next to each component of physical fitness to indicate that you have attempted the activity. Lab 6B Chart 1  Physical Fitness Activities Agility Estimating Your Fitness Body Composition 7. Paper ball pickup. Place two wadded paper balls on the 1. The pinch. Have a partner floor 5 feet away. Run until pinch a fold of fat on the back both feet cross the line, pick of your upper arm (body fatness), up the first ball, and return halfway between the tip of the both feet behind the starting elbow and the tip of the shoulder. line. Repeat with the second ball. Finish in 5 seconds. Men: no greater than 3/4 inch Balance Women: no greater than 1 inch 8. One-foot balance. Stand on Cardiorespiratory Endurance one foot; press up so that the weight is on the ball of the 2. Run in place. Run in place for foot with the heel off the floor. 11⁄2 minutes (120 steps per minute). Hold the hands and the other Rest for 1 minute and count the leg straight out in front for heart rate for 30 seconds. A heart 10 seconds. rate of 60 (for 30 sec.) or lower passes. A step is counted each Coordination time the right foot hits the floor. 9. Paper ball bounce. Wad up a Flexibility sheet of notebook paper into a ball. Bounce the ball back and 3. Backsaver toe touch. Sit on the forth between the right and left floor with one foot against a wall. hands. Keep the hands open Bend the other knee. Bend forward and palms up. Bounce the ball at the hips. After three warm-up three times with each hand (six trials, reach forward and touch your times total), alternating hands closed fists to the wall. Bend forward for each bounce. slowly; do not bounce. Repeat with the other leg straight. Pass if fists Reaction Time touch the wall with each leg straight. 10. Paper drop. Have a partner Muscular Endurance hold a sheet of notebook paper so that the side edge 4. Side leg raise. Lie on the floor on is between your thumb and your side. Lift your leg up and to index finger, about the width the side of the body until your feet of your hand from the top of are 24 to 36 inches apart. Keep the the page. When your partner knee and pelvis facing forward. Do drops the paper, catch it not rotate so that the knees face before it slips through the the ceiling. Perform 10 with each leg. thumb and finger. Do not lower your hand to catch the paper. Power Speed 5. Standing long jump. Stand with the toes behind a line. Using no 11. Double-heel click. With the run or hop step, jump as far as feet apart, jump up and tap the possible. Men must jump their heels together twice before height plus 6 inches. Women must you hit the ground. You must jump their height only. land with your feet at least 3 inches apart. Strength 6. Push-up. Lie face down on the floor. Place the hands under the shoulders. Keeping the legs and body straight, press off the floor until the arms are fully extended. Women repeat once; men, three times. 96

The Physical Activity Pyramid  c  Section III Concept 7 Moving from Inactivity to Moderate-Intensity Active Lifestyles LEARNING OBJECTIVES After completing the study of this Concept, you will be able to: c Define moderate physical activity and differentiate it from light and vigorous physical activity. c Describe the health benefits of moderate physical activity, and explain why moderate physical activity is the most popular form of physical activity. c Describe and explain the FIT formula for moderate physical activity. c Plan a personal moderate physical activity program based on SMART goals, and self-monitor your plan. c Evaluate your current environment and determine ways to modify it to encourage moderate physical activity. c Describe the risks associated with inactivity, including excessive sitting. Inactivity has many health risks that can be overcome with regular moderate-intensity physical activity. 97

98 Section 3  c  The Physical Activity Pyramid Humans are clearly meant to move, but the nature of our different types of physical activity (Figure 1). The activi- society has made it difficult for many people to lead ties in the pyramid provide health, wellness, and fitness active lifestyles. Cars, motorized golf carts, snowblowers, benefits that we will describe in detail. However, it is now elevators, remote control devices, and email are just some clear that physical inactivity presents of the modern conveniences that have reduced the amount of a risk to a person’s health, indepen- activity in our daily lives. dent of the level of activity. In other Finding ways to get regular physical activity is critical words, there are health risks even for VIDEO 1 for optimal health and wellness, but it is now clear that active people who sit too much. The avoiding inactivity is also important. In fact, evidence sug- words “Avoid Inactivity” are included in bold black type gests that excessive inactivity (especially too much sitting) below the pyramid to illustrate the importance of minimiz- puts your health at risk even if you are physically active. In ing inactivity. this Concept, you will learn about the risks of inactivity as National guidelines for children indicate that periods well as the benefits of moderate-intensity physical activity. of inactivity should be less than 2 hours. A specific goal of You will also learn strategies to help you avoid sedentary Healthy People 2020 is to reduce the proportion of youth living and to help you incorporate moderate activity into who are inactive for long periods of time (defined as view- your daily routine. ing television and videos or playing computer games more than 2 hours a day). These recommendations are targeted to help minimize sedentary time in youth, but evidence of harm Moving from Inactivity from inactivity is even stronger in adults. An editorial in to Active Living the British Journal of Sports Medicine suggests that sitting for hours provides “harmful signals” to the body’s systems. Inactivity can be hazardous to your health. The The potential harm from sedentary living has now become five steps in the physical activity pyramid illustrate the widely popularized in the media as numerous groups have jumped onto the phrase “sitting is the new smoking.” Energy Balance To reduce risks of inactiv- Energy Out Energy In ity, it is important to minimize (Activity) (Diet) the total amount of sedentary time and to include periodic breaks in sitting by standing up and moving about more often. Flexibility • Yoga Obtaining physical activity STEP 5 Exercises • Stretch from the five steps of the physi- cal activity pyramid is ideal, but minimizing time spent STEP 4 Muscle • Calisthenics being sedentary provides inde- Fitness • Resistance pendent benefits. Implications Exercises exercise for health are described later in this Concept and benefits for STEP 3 Vigorous Sports • Tennis weight control are covered in and Recreation • Hike other Concepts. You will assess sedentary behavior in Lab 7B. • Jog STEP 2 Vigorous • Bike Moderate physical activity Aerobics • Aerobic dance is the foundation of an active lifestyle. Moderate physical activity is included at STEP 1 Moderate • Walk the base of the physical activ- Physical Activity • Yard work ity pyramid (see Figure 1) • Golf because it can be performed by virtually all people, regardless of fitness level or age. Mod- Avoid Inactivity erate activities include some Figure 1  c  The physical activity pyramid, step 1: moderate physical activity. activities of daily living as well as less intense sports and Source: C. B. Corbin.

Concept 7  c  Moving from Inactivity to Moderate-Intensity Active Lifestyles    99 Table 1  c  Classification of Physical Activity Intensities for Generally Healthy Adults Classification Intensity Range Examples Sedentary 1.0–1.5 METs Light 1.5–3.0 METs Sitting, lying Moderate 3.0–6.0 METs Showering, grocery shopping, playing Vigorous .6.0 METs musical instrument, washing dishes Walking briskly, mowing lawn, playing table tennis, doing carpentry Hiking, jogging, digging ditches, playing soccer Brief walks throughout the day can help you meet recommended be maintained as easily unless a person has a good level of levels of moderate activity. fitness. Examples include more structured aerobic activi- ties (e.g., jogging, biking, swimming) or vigorous sports recreational activities. Taking a brisk walk is a simple and (e.g., soccer). Activities below 3.0 METs can be classi- logical way to incorporate moderate activity into daily liv- fied as “light intensity” but researchers now distinguish ing. However, activities of daily living, such as walking the light activity (1.5  to 3.0 METs) from sedentary activity dog, gardening, mowing the lawn, carpentry, or housework (1.0 to 1.5 METs), which primarily captures sitting and lying can count as moderate activities. Moderate sports and rec- time. Examples of light activities include lower-intensity reational activities not considered to be vigorous enough to activities of daily living such as showering, grocery shop- be placed at step 3 of the physical activity pyramid can also ping, washing dishes, and casual walking. Distinctions be  used to meet the moderate physical activity guideline among the types of activities are summarized in Table 1. (e.g., playing catch, shooting baskets, recreational bike rid- ing, and casual rollerblading). Because moderate activities are relatively easy to perform, they are popular among adults. Walking is Moderate physical activity can be distinguished from the most popular of all leisure-time activities among adults. “light” activity and “vigorous” activity. Scientists have Women walk more than men, and young adults (18–29) devised a method to classify levels of activity by intensity. walk less than older adults, probably because of more With this system, all activities are compared against the amount of energy expended at rest. Moderate Physical Activities  Activities equal in intensity to brisk walking; activities three to six times as intense as lying or Resting energy expenditure is defined as 1 “metabolic sitting at rest (3–6 METs), also referred to as moderate-intensity equivalent” or 1 MET. Other activities are then assigned physical activity. values in multiples of METs. For generally healthy adults, MET  One MET equals the amount of energy a person expends at moderate-intensity activities require an energy expenditure rest. METs are multiples of resting activity (2 METs equal twice of 3.0 to 6.0 METs. This means that they require between the resting energy expenditure). three and six times the energy expended while at rest. Vigorous Physical Activities Activities that are more vigor- Moderate-intensity activities are often referred to as aerobic ous than moderate activities with intensities at least six times as physical activities because the aerobic metabolism can typi- intense as lying or sitting at rest (.6 METs). cally meet the energy demand of the activity. This allows Light Activities Activities that involve standing and/or slow moderate-intensity (aerobic) activities to be performed com- movements with intensities 1.5 to 3 times as intense as lying or fortably for extended periods of time by most people. sitting at rest (1.5–3.0 METs). Sedentary Activities  Activities that involve lying or sitting Activities above 6 METs are considered to be with intensities similar to (or just slightly higher) than rest vigorous physical activities, and these cannot usually (1.0–1.5 METs).

100 Section 3  c  The Physical Activity Pyramid Table 2  c  Classification of Moderate Physical Activities for People of Different Fitness Levels Activity Classification by Fitness Level Sample Lifestyle Activities Low Fitness Marginal Fitness Good Fitness High Performance Light Very light Washing your face, dressing, Very light/light Very light typing, driving a car Moderate Light Moderate Light Normal walking, walking Vigorous Moderate downstairs, bowling, mopping Moderate/vigorous Moderate Brisk walking, lawn mowing, shoveling, social dancing involvement in sports and other vigorous activities. As many in England had more health problems than conductors who as 40  to 50 percent of adults say they walk, but less than climbed the stairs during the day to collect the tickets. The half that number report walking 30 minutes or more at least studies controlled for other lifestyle factors, so the improved 5 days a week. health was attributed to the extra activity accumulated throughout the day. Since then, hundreds of studies have fur- While overall activity levels tend to decline with age, ther confirmed the importance of moderate activity for good involvement in lifestyle activity actually tends to increase. health. However, additional health benefits are possible if This is because many older adults move away from vigorous vigorous physical activity is also performed. sports and recreation and spend more time in lifestyle activi- ties, such as gardening and golf. Older adults tend to have Moderate activity promotes metabolic fitness. Meta- more time and money for these types of recreational activi- bolic fitness is fitness of the systems that provide the energy ties, and the lower intensity may be appealing. for effective daily living. Indicators of good metabolic fitness include normal blood lipid levels, normal blood The advantage of moderate activity is that there are many pressure, normal blood sugar levels, and healthy body fat opportunities to be active. Finding enjoyable activities that levels. Moderate physical activity promotes metabolic fit- fit into your daily routine is the key to adopting a more ness by keeping the metabolic system active. Building and active lifestyle. maintaining cardiorespiratory endurance requires a regular Activity classifications vary, depending on one’s level challenge to the cardiovascular system, and building meta- of fitness. Normal walking is considered light activity for bolic fitness requires a similar regular challenge to the met- a person with good fitness (see Table 2), but for a person abolic system. Individuals with good levels of fitness will with low to marginal fitness the same activity is considered receive primarily metabolic fitness benefits from moder- moderate. Similarly, brisk walking may be a vigorous activ- ate activity, but those with low fitness will likely receive ity (rather than moderate) for individuals with low fitness. metabolic and cardiorespiratory endurance benefits. Moder- Table 2 helps you determine the type of lifestyle activity ate activity is particularly important for the large segments considered moderate for you. Beginners with low fitness of the population that do not participate in other forms of should start with normal rather than brisk walking, for regular exercise. As previously described, some activity is example. In later Concepts you will learn to assess your cur- clearly better than none. rent fitness level. You may want to refer back to Table 2 after you have made self-assessments of your fitness. Moderate physical activity has wellness benefits. The health benefits from physical activity are impressive, but the The Health and Wellness Benefits wellness benefits may have a bigger impact on our daily of Moderate Physical Activity lives. Numerous studies have shown that physical activity is associated Moderate activity provides significant health benefits. with improved quality of life (QOL), Research has clearly shown that even modest amounts of but it has proven difficult to determine VIDEO 2 moderate activity have significant health benefits. Two early studies paved the way for this line of research. One the contributing factors or underlying study reported that postal workers who delivered mail mechanisms. The influence may be due to reduced stress, had fewer health problems than workers who sorted mail. improved cognition, better sleep, improved self-esteem, Another study reported that drivers of double-decker buses reduced fatigue, or (more likely) a combination of many dif- ferent effects. Research suggests that college students who

Concept 7  c  Moving from Inactivity to Moderate-Intensity Active Lifestyles    101 are more physically active have more positive feeling states How Much Moderate Physical (“pleasant-activated feelings”) than students who are less Activity Is Enough? physically active, even after controlling for sleep and previ- ous days’ activity and feeling states. They also noted that There is a FIT formula for moderate physical activity. feeling states improved on days when people reported per- The term “threshold of training” is used to describe the forming more activity than normal. The wellness benefits minimum activity needed for benefits. As described in can impact young people every day, whereas health benefits other Concepts, public health guidelines endorsed by the may not be noticed until a person gets older. ACSM, the AHA, and the CDC have recommended that adults accumulate 150 minutes of moderate-intensity activ- Regular activity is important to achieving health, ity each week, an amount equal to 30 minutes 5 days a week. wellness, and fitness benefits. For the benefits of activ- The recommendation highlighted in the original Surgeon ity to be optimal, it is important to exercise regularly. The General’s Report on Physical Activity called for adults to specific benefits from moderate activity tend to be more accumulate about 1,000 kcal/week (or about 150 kcal/day) dependent on frequency than on intensity. This is some- from moderate activity. Table 3 summarizes the threshold times referred to as the last bout effect, because the effects levels for frequency, intensity, and time (duration). Note are short term (i.e., attributable to the last bout of activ- that these are considered minimal, or threshold, levels. The ity performed). For example, regular exercise promotes target zone calls for the accumulation of 30 or more minutes metabolic fitness by creating the stimulus that helps main- a day. Physical activity above the recommended minimum tain insulin sensitivity and improve glucose regulation. provides additional health benefits. Another example is the beneficial effect of exercise on Vigorous activity can substitute for moderate activity. stress management. In this case, the periodic stimulus from The U.S. Physical Activity Guidelines provide some flex- exercise helps directly counter the negative physical and ibility for meeting activity guidelines. Rather than requir- physiological responses to stress. To maximize the benefits ing activity on 5 different days, the guidelines specify that of physical activity, it is important to try to get some activ- 150 minutes of moderate physical activity can be accumu- ity every day. lated during the week. If you fail to meet the 30-minute guideline on 1 day, you can make it up on another and still Sustained light-intensity activity may provide health meet the guideline. Vigorous-intensity activity can also benefits and promote weight control. The new physical be substituted to meet the weekly targets. According to activity guidelines have recommended that activities be at the guidelines, each minute of vigorous activity counts as least moderate in intensity. However, 2 minutes of moderate activity. Therefore, the guideline can evidence suggests that the accumu- lation of light-intensity activity can Metabolic Fitness Benefits  Improvements in metabolic func- have benefits, especially in those who VIDEO 3 tion that reduce risks of diabetes and metabolic syndrome. Wellness Benefits  Increases in quality of life and well-being. are sedentary. Some researchers have Last Bout Effect A short-term effect associated with the last referred to this type of activity as Non-Exercise Activity bout of activity. Typically related to improvements in metabolic Thermogenesis (NEAT) to emphasize the substantial number fitness. of calories that can be burned by performing light-intensity activity. Meeting the recommendation for moderate activity is best, but light activity breaks up sedentary time and keeps the metabolism more active. Table 3  c  The FIT Formula for Moderate Physical Activity Threshold of Training (minimum)a Target Zone (optimal) Frequency At least 5 days a week 5–7 days a week Intensityb • Equal to brisk walkingb • Equal to brisk to fast walkingb • Approximately 150 calories accumulated per day • Approximately 150–300 calories accumulated per day • 3 to 5 METsb • 3 to 6 METsb Time (duration)c 30 minutes or three 10-minute sessions per day 30–60 minutes or more accumulated in sessions of at least 10 minutes aThe recommendation of 150 minutes can be accumulated throughout the week, but these thresholds provide a good target. bHeart rate and relative perceived exertion can also be used to determine intensity. cDepends on fitness level (see Table 2).

102 Section 3  c  The Physical Activity Pyramid HELP Health is available to Everyone Monitoring Physical Activity for a Lifetime, and it’s Personal Behavior Walking is by far the most commonly reported moder- ate activity, but some people often go out of their way to A variety of methods can be used to accumulate avoid walking (such as waiting for campus buses, driving moderate physical activity for health benefits. Finding around parking lots to get closer to a store, or taking an 30 minutes or longer for continuous physical activity may be elevator rather than climbing a few flights of stairs). difficult, especially on very busy days. However, the physi- Do you view walking as a “means to an end” (i.e., simply cal activity guidelines emphasize that moderate activity can as a way to get around) or as an “end in itself” (i.e., as be accumulated throughout the day. Figure 2 illustrates the a way to get more physical activity)? How might this activity profiles for three different people. The red line pro- perception influence your activity patterns? files a person who is inactive except for brief walks from the car to the office in the morning and from the office to ACTIVITY the car in the evening. This person is sedentary and does not meet the also be met by performing 75 minutes of vigorous activity moderate activity guidelines. Because instead of 150 minutes of moderate activity. some activity is better than none, the VIDEO 4 The guidelines can also be expressed in total “MET- brief walks are better than no activity minutes.” To compute MET-minutes, you simply multiply the at all. The blue line represents a person who is sedentary MET level of the activity you performed by the number of most of the day but meets the moderate activity guideline minutes. For example, a 60-minute brisk walk (approximately by taking a long walk during the noon hour. The green line 3 METs) would yield 180 MET-minutes (3 METs 3 60 min- represents the activity of a person who meets the moderate utes). However, note that this same volume can also be activity standard in multiple bouts, including lifestyle activi- achieved with a 30-minute run that requires approximately ties such as walking to and from work, walking to lunch, 6 METs (6 METs 3 30 minutes). A total of 500 MET-minutes and climbing the stairs. You can accumulate activity using per week is recommended to meet the minimum guidelines. the method that you prefer as long as you meet the recom- mended guidelines. Activity bouts of 10 minutes are recommended, but shorter durations of moderate activity have benefits. Energy expenditure can be used to monitor physical National physical activity guidelines suggest that moderate activity. As shown in Table 3, an energy expenditure of activity bouts should be 10 minutes in length or longer for opti- between 150 and 300 kcal/day from physical activity is suf- mal health and fitness benefits. Nevertheless, short-duration ficient for meeting physical activity guidelines. While not moderate activity, sometimes referred to as “incidental physi- as simple as tracking time, calories expended from physi- cal activity,” accumulated throughout the day is also beneficial. cal activity can be estimated if the approximate MET value The specification of 10-minute sessions in the guidelines is of the activity is known. The energy cost of resting energy somewhat arbitrary as there is no absolute threshold defining expenditure (1 MET) is approximately 1 calorie per kilogram how long activity sessions must be. In general, the main focus of body weight per hour (1 kcal/kg/hr). An activity such as should be on the total volume of moderate activity performed. brisk walking (4 mph) requires an energy expenditure of about 4 METs, or 4 kcal/kg/hr. A 150-lb person (~70 kg) Special moderate activity guidelines have been walking for an hour would expend about 280 kcal (4 kcal/ developed for children, older adults, and adults with kg/hr 3 70 kg 3 1 hr). Note that a 30-minute walk would chronic health conditions. Guidelines for physical activ- burn approximately 150 calories and satisfy the guideline. ity depend on the unique needs of the target population. Children need more physical activity than adults (at least Commercial fitness equipment can provide energy expen- 60 minutes and up to several hours of activity each day). diture estimates. The devices use an estimated MET level based on the selected intensity or a measured heart rate Guidelines are also different for older adults and adults (if a heart rate sensor is used). The timer on the machine with chronic conditions. As previously described (see then tracks the time of the workout, and this allows calo- Table 2), activity that is moderate for young adults may be ries to be estimated during the workout. The estimate will too intense for some older individuals or those with health be somewhat accurate only if the machine also obtained a problems. Because of this, the guidelines recommend that body weight value during the setup process. If this wasn’t these individuals focus on tracking minutes of activity. This obtained, the calorie estimates are probably based on some allows the intensity to be a self-determined level that cor- reference value of weight and therefore may not be accurate. responds to a person’s relative level of fitness. Table 4 lists estimated METs for different activities, along with calorie estimates (per hour of exercise) for people of different body weights.

Concept 7  c  Moving from Inactivity to Moderate-Intensity Active Lifestyles    103 Energy expenditure (METs) Sedentary Vigorous 6 Moderate Walk to car Walk to car 3 noon 1 2 3 4 5 6 7 8 9 10 11 Light 1 Time (hours) PM 0 6 7 8 9 10 11 AM Energy expenditure (METs) Moderate lifestyle activity Vigorous 6 Walk Work Work Walk Moderate to bus to bus 3 Light 1 0 noon 1 2 3 4 5 6 7 8 9 10 11 6 7 8 9 10 11 AM Time (hours) PM Energy expenditure (METs) Moderate structured activity Vigorous Noon-hour treadmill walk 6 Moderate 3 Light 1 0 6 7 8 9 10 11 noon 1 2 3 4 5 6 7 8 9 10 11 AM PM Time (hours) Figure 2  c  Comparison of people performing moderate activity in different ways.

104 Section 3  c  The Physical Activity Pyramid Table 4  c  Calories Expended in Lifestyle Physical Activities Calories Used per Hour for Different Body Weights Activity Classification/Description METsa 100 lb 120 lb 150 lb 180 lb 200 lb 220 lb Gardening Activities (45 kg) (55 kg) (70 kg) (82 kg) (91 kg) (100 kg)   Gardening (general) 5.0 227 273 341 409 455 502    Mowing lawn (hand mower) 6.0 273 327 409 491 545 599    Mowing lawn (power mower) 4.5 205 245 307 368 409 450   Raking leaves 4.0 182 218 273 327 364 401   Shoveling snow 6.0 273 327 409 491 545 599 Home Activities   Child care 3.5 159 191 239 286 318 350    Cleaning, washing dishes 2.5 114 136 170 205 227 249   Cooking/food preparation 2.5 114 136 170 205 227 249   Home/auto repair 3.0 136 164 205 245 273 301   Painting 4.5 205 245 307 368 409 450    Strolling with child 2.5 114 136 170 205 227 249   Sweeping/vacuuming 2.5 114 136 170 205 227 249   Washing/waxing car 4.5 205 245 307 368 409 450 Leisure Activities   Bocci ball/croquet 2.5 114 136 170 205 227 249   Bowling 3.0 136 164 205 245 273 301   Canoeing 5.0 227 273 341 409 455 501    Cross-country skiing (leisure) 7.0 318 382 477 573 636 699   Cycling (,10 mph) 4.0 182 218 273 327 364 401    Cycling (12–14 mph) 8.0 364 436 545 655 727 799   Dancing (social) 4.5 205 245 307 368 409 450   Fishing 4.0 182 218 273 327 364 401   Golf (riding) 3.5 159 191 239 286 318 350   Golf (walking) 5.5 250 300 375 450 500 550   Horseback riding 4.0 182 218 273 327 364 401   Swimming (leisure) 6.0 273 327 409 491 545 599   Table tennis 4.0 182 218 273 327 364 401    Walking (3.5 mph) 3.8 173 207 259 311 346 387 Occupational Activities   Bricklaying/masonry 7.0 318 382 477 573 636 699   Carpentry 3.5 159 191 239 286 318 350   Construction 5.5 250 300 375 450 500 550   Electrical work/plumbing 3.5 159 191 239 286 318 350   Digging 7.0 318 382 477 573 636 699   Farming 5.5 250 300 375 450 500 550   Store clerk 3.5 159 191 239 286 318 350   Waiter/waitress 4.0 182 218 273 327 364 401 Note: MET values and caloric estimates are based on values listed in Compendium of Physical Activities. aBased on values of those with “good fitness” ratings.

Concept 7  c  Moving from Inactivity to Moderate-Intensity Active Lifestyles    105 Step counts can help monitor physical activity patterns. There are some limitations in using steps as indicators Steps have become a popular and well-understood metric to of total physical activity. A person with longer legs will quantify physical activity. Digital pedometers have been used accumulate fewer steps over the same distance than some- for years to provide an easy way for people to track steps, one with shorter strides (due to a lon- but step counts can be reported on other monitoring devices, ger stride length). A person running including smartphone apps. Steps provide a good indica- will also accumulate fewer steps over tor of activity for most people since most forms of activity the same distance than a person who VIDEO 5 involve some locomotor movement (major exceptions would be swimming and cycling). The ability to easily monitor daily walks. There is considerable vari- step counts provides a helpful reminder to many people about ability in the quality (and accuracy) of monitors and step the importance of being active during the day. counting apps so it is also important to consider this when interpreting data. Studies on large numbers of people provide data to help classify people into activity categories based on step counts (see Table 5), but it is beneficial to set goals on your own baseline. Wear the pedometer (or similar monitoring device) for 1 week to establish a baseline step count (average steps per day). Then, set a goal of increasing steps per day by 1,000 to 3,000 steps. Keep records of daily step counts to help you determine if you are meeting your goal. Setting a goal that you are likely to meet will help you find success. As you meet your goal, increase your step counts gradually. Table 5  c  Activity Classification for Pedometer Step Counts in Healthy Adults Category Steps/Day ,5,000 Sedentary 5,000–6,999 7,000–9,999 Low active 10,000–12,500 .12,500 Somewhat active Threshold Active Target Zone Very active Smart phone apps provide feedback to help track active and Source: Based on values from Tudor-Locke. sedentary time. In the News Smartphone Apps for Self-Monitoring The integration of consumer health tools and inactivity. The  display features three concentric rings: the applications provides a prime battleground “Exercise” ring is completed when you accumulate 30 minutes for smartphone manufacturers and developers. There has of physical activity, and the “Stand” ring is completed if been considerable media coverage on the Apple Health Kit you have at least some movement in each of the 12 waking/ and the Google Fit—platforms that have spurred new innova- active hours in the day. (See link in Suggested Resources and tions and app development—and “smartwatches” that provide Readings.) real-time information about a variety of health-related data Do you think this type of feedback would help you to develop tracked on the phones. The Apple Watch, for example, was and sustain a more active, less sedentary lifestyle? designed to specifically help promote activity and minimize ACTIVITY

106 Section 3  c  The Physical Activity Pyramid Adopting and Sustaining an Active Identity TECHNOLOGY UPDATE Seek ways to reduce and/or break up sedentary time. Standing Desks and Treadmill Desks Much time in our daily lives is spent being sedentary (e.g., readi­ng/studying, working at computers, driving in cars, eat- Advancements in office furniture have enabled people to be ing). A key for healthy living (and weight control) is to mini- less sedentary while at work. For example, electronic desks mize time spent being sedentary. The popularity of standing allow standard sitting desks to transform into “standing desks” desks has increased in recent years as a way to promote with the push of a button. A company called TrekDesk sells more activity at work (see Technology Update). Minimiz- desks that mount over standard treadmills to enable people ing time spent watching television or standing while on the to walk while they work. These devices offer considerable phone can also help to reduce total sedentary time. The neg- potential for promoting activity in worksite settings. (See www. ative effects of sedentary time can also be minimized with trekdesk.com) periodic breaks. Research suggests that the risks are due to Would you take advantage of an active workstation if it prolonged sitting, so take periodic standing breaks. was available on campus or at your work setting? Why or why not? Seek out and promote active environments. Most people would like to be more active, but the nature of our ACTIVITY society and our environment often makes this difficult. Studies have demonstrated conclusively that the physical, or built, environment has important influences on physical activity patterns, but ultimately you must take responsibil- ity for your lifestyle and find ways to be active. The key is to take stock of your lifestyle (and your environment) and determine ways to take advantage of what is available. Building active community environments has become an important national priority. Many public health organi- zations have developed awareness campaigns and strong advocacy networks to support the creation of healthier environments. The vision is for neighborhoods that allow physical activity to be built into a person’s normal rou- tine (going to the store, visiting friends) and communities with integrated biking and walking paths. These concepts are consistent with other recommendations for urban plan- ning (e.g., Smart Growth Movement). Groups such as the National Coalition of Walking Advocates, the Alliance for Biking and Walking, and Walkable Communities play key roles in promoting awareness and advocating at the state A CLOSER LOOK Every Body Walk and opportunities to network and share stories. The website (www.everybodywalk.org) features a hub for walking-related Every Body Walk is a national movement committed to “get blogs and video clips showing how groups across America are Americans up and moving.” The organization has developed a finding a new sense of community through walking. variety of social media applications that help to connect organi- zations, people, and communities across the country. Custom- Does the social norm influence your perception of physical ized (free) apps for smartphones are available to help track and activity? Can social media tools lead to changes in the social personalize your walking plan, connect with walking communi- norm? ties, and share stories. Associated Facebook links and Twitter feeds (follow @everybodywalk) provide inspirational messages ACTIVITY

Concept 7  c  Moving from Inactivity to Moderate-Intensity Active Lifestyles    107 to be a local advocate for walkability and bikeability issues in your community. Seek out ways to add physical activity into your day. Active commuting is one way to add physical activity to your lifestyle. It takes additional preparation and the logistics can be challenging, but it is a great way to build activity into your day. In addition to providing beneficial amounts of physi- cal activity, this can save time, reduce gas, save money, and help the environment. Another option is to take more active trips to the store. Research suggests that the overwhelming majority of our car trips are 1 mile or less. Walking or biking even a few of these trips can have a big impact. The abil- ity to walk or bike to work or to the store may not be pos- sible for you because of the nature of your community or the safety of the roads. However, there are a number of other strategies you can use to get more activity in your day. Consider parking farther away from VIDEO 6 store entrances, using the stairs rather than the elevator, taking walking breaks, and even standing (instead of sitting) when convenient. Adopting an active life- Bike commuting is an effective way to add physical activity to style in a sedentary society is challenging, but it is within your day. your control. and national levels to improve federal practices and funding Built Environment  A term used to describe aspects of our cre- decisions that influence biking and walking. These groups ated physical environment (e.g., buildings, roads). encourage community activism since consumers ultimately influence social norms and decision making. Seek out ways Strategies for Action A regular plan of moderate physical helps you keep a log of moderate activities (or step counts), activity is a good place to start. Mod- it also lets you hone your self-management skills. Charts like erate physical activity is something that virtually anyone can do. this can be copied to make a log book for long-term activity In Lab 7A, you can set moderate physical activity goals and plan self-monitoring. a 1-week lifestyle physical activity program. For some people, this plan may be the main component of a lifetime plan. For others, it Self-monitoring of sedentary behavior can help you minimize may be only a beginning that leads to the selection of activities sedentary time. In Lab 7B, you will conduct an assessment of from other levels of the physical activity pyramid. Even the most your sedentary behavior. You will determine time spent being active people should consider regular moderate physical activity inactive and also calculate a Sedentary Behavior Index based because it is a type of activity that can be done throughout life. on the ratio of your sedentary to light activity. Reducing time spent in sedentary behavior takes conscious effort, but the lab Self-monitoring moderate physical activity can help you will provide a way to examine it. stick with it. The self-monitoring chart in Lab 7A not only ACTIVITY

108 Section 3  c  The Physical Activity Pyramid Suggested Resources ∙ Chau, J. Y., Daley, M., Dunn, S., Srinivasan, A., Do, A., Bauman, and Readings A. E., & van der Ploeg, H. P. (2014). The effectiveness of sit-stand workstations for changing office workers’ sitting time: Results from the Stand@Work randomized controlled trial pilot. International The websites for the following sources can be accessed by searching Journal of Behavior, Nutrition and Physical Activity, 11, 127 (pdf). online for the organization, program, or title listed. Specific scien- tific references are available at the end of this edition of Concepts of ∙ Dunlop, D., et al. (2013). Sedentary time in U.S. older adults Fitness and Wellness. associated with disability in activities of daily living independent of physical activity. Journal of Physical Activity and Health. ∙ ACSM. (2014). ACSM’s Guidelines for Exercise Testing and Published online, November 12, 2013. Prescription (9th ed.). Philadelphia: Lippincott, Williams & ∙∙ Just Stand.org: Sit Less, Stand More, Start Now (pdf). Wilkins. Levine, J. A. (2014). Get Up! Why Your Chair Is Killing You and ∙∙∙∙∙ Active Living Research MOVE: A Blog About Active Living. What You Can Do About It. New York: Palgrave Macmillan. American College of Sports Medicine: Physical Activity 360. American College of Sports Medicine: Sit Less/Move More (pdf). ∙ National Sporting Goods Association. (2014). Sports Participation American Heart Association: Sitting Less for Adults (pdf). in the US. Bureau of Labor Statistics: American Time Use Survey. ∙ U.S. Department of Health and Human Services. (2008). Physical Activity Guidelines for Americans. Washington, DC.

Lab 7A  Setting Goals for Moderate Physical Activity Lab 7A and Self-Monitoring (Logging) Program Name Section Date Purpose: To set moderate activity goals and to self-monitor (log) physical activity. Procedures SanedttiSneglfG-MoaolnsitfoorrinMgo(dLeorgagteinPg)hPysroicgarlaAmctivity 1. Read the five stages of change questions below. Place a check by the stage that best represents your current moder- ate physical activity level. If you are at stages 1–3 (precontemplation, contemplation, or preparation), you may want to set goals below the threshold of 30 minutes per day to get started. Those at the action or maintenance stage should consider goals of 30 minutes or more per day. 2. Determine moderate activity goals for each day of a 1-week period. In the columns (Chart 1) under the heading “Moderate Activity Goals,” record the total minutes per day that you expect to perform OR the total steps per day that you expect to perform. Record the specific date for each day of the week in the “Date” column. 3. The goals should be realistic for you, but try to set goals that would meet current physical activity guidelines. If you choose step goals, you will need a pedometer. Use Table 5 on page 105 to help you to choose daily step goals. 4. If you choose minutes per day as your goals, use Chart 2 to keep track of the number of minutes of activity that you perform on each day of the 7-day period. Record the number of minutes for each bout of activity of at least 10 minutes in length performed during each day (Chart 2). Determine a total number of minutes for the day and record this total in the last column of Chart 2 and in the “Minutes Performed” column of Chart 1. 5. If you choose steps per day as your goals, determine the total steps per day accumulated on the pedometer and record that number of steps in the “Steps Performed” column for each day of the week (Chart 1). 6. Answer the questions in the Conclusions and Implications section (use full sentences for your answers). Determine your stage for moderate physical activity. Check only the stage that represents your current moderate activity level. Precontemplation: I do not meet moderate activity guidelines and have not been thinking about starting. Contemplation: I do not meet moderate activity guidelines but have been thinking about starting. Preparation: I am planning to start doing regular moderate activity to meet guidelines. Action: I do moderate activity, but I am not as regular as I should be. Maintenance: I regularly meet national goals for moderate activity. Chart 1  Moderate Physical Activity Goals and Summary Performance Log Select a goal for each day in a 1-week plan. Keep a log of the activities performed to determine if your goals are met. Moderate Activity Goals Summary Performance Log Date Minutes/Day Steps/Day Minutes Performed Steps Performed Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 109

Chart 2  Moderate Physical Activity Log (Daily Minutes Performed) If you choose minutes per day as goals, write the number of minutes for each bout of moderate activity performed each day. Record a daily total (total minutes of moderate activity per day) in the “Daily Total” column. Record daily totals in Chart 1. Lab 7A Moderate Activity Bouts of 10 Minutes or More Date Bout 1 Bout 2 Bout 3 Bout 4 Bout 5 Daily Total SettinagndGoSaellfs-fMoroniMtoordienrgat(LeoPghgyisnigc)alPrAoctgirvaitmy Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Did you meet your moderate activity goals for at least 5 days of the week? Yes No Do you think you can consistently meet your moderate activity goals? Yes No What activities did you perform most often when doing moderate activity? List the most common activities in the spaces below. Conclusions and Interpretations 1. Do you feel that you will use moderate physical activity as a regular part of your lifetime physical activity plan, either now or in the future? Use several sentences to explain your answer. 2. Did setting goals and logging activity make you more aware of your daily moderate physical activity patterns? Explain why or why not. 110

Lab 7B  Estimating Sedentary Behavior Name Section Date Lab 7B Purpose: To estimate time spent in sedentary behavior. Procedures 1. Pick a day of the week to evaluate. Sedentary Behavior Index Rating Chart 2. Use the Sedentary Behavior Assessment on the next page to estimate the time spent in different intensities of Estimating Sedentary Behavior activity during the day. Sedentary Behavior Index Sedentary/Light Ratio 3. Summarize the results for the time spent in each cate- Low Sedentary ,1 gory and be sure your daily total 5 24 hours. 4. Calculate the ratio of sedentary to light activity and use Moderate Sedentary 1.0–2.0 the Rating Chart to determine your Sedentary Behav- High Sedentary .2.0 ior Index. Note: There are no absolute guidelines, but a smaller ratio is desirable. Sedentary Break Index Average Break Score 5. Calculate the average breaks in sedentary time across Frequent Breaks 4–5 the five categories and use the Rating Chart to determine your Sedentary Break Index. Note: There are no abso- Moderate Breaks 2–3 lute guidelines, but a larger number of average breaks is Infrequent Breaks 0–1 desirable. 6. Record your scores and the indexes in the Results section. 7. Answer the questions in the Conclusions and Implications section. Results Summarize your activity/inactivity profile by completing the following: Sleep Time (hr) 5 __________ Sleep % 5 __________ Sedentary Time (hr) 5 __________ Sedentary % 5 __________ Light Time (hr) 5 __________ Light % 5 __________ Moderate Activity Time (hr) 5 __________ Moderate % 5 __________ Vigorous Activity Time (hr) 5 __________ Vigorous % 5 __________     Total Hours 5 __________ Sedentary/Light Ratio 5 __________ Average Break Score 5 __________ Sedentary Behavior Index 5 __________ Sedentary Break Index 5 __________ Conclusions and Implications: Summarize the overall assessment of your sedentary behaviors by describing both the total time you spend sedentary and the calculated sedentary/light ratio. Comment on the frequency of breaks in sedentary behavior and explain how changing the frequency of your breaks would influence your Sedentary Behavior Index. Do you feel you are effectively minimizing sedentary time, or do you think you may have room for improvement? Based on categories and constructs used in the Workforce Sitting Questionnaire (Chau et al., 2011). 111

Lab 7B Sedentary Behavior Assessment (complete these steps in order): 1. Estimate the total time you spend in sedentary or light activity (Sedentary 1 Light) by subtracting from 24 (hours) the estimated time you spend (in hours) sleeping, engaged in moderate physical activity (MPA), and engaged in vigorous physical activity (VPA). The formula below will give you an estimate of the combined time spent in sedentary or light activities. Sedentary 1 Light (hr) 5 24 2 2 25 Sleep (hr) MPA (hr) VPA (hr) Sedentary 1 Light 2. Estimate the time you spend being sedentary (i.e., sitting or lying) in five major categories or settings and then sum for the whole day. For each category, estimate the frequency of breaks in the sedentary behavior for that category. Estimating Sedentary Behavior The categories below represent key Estimate the total time spent sitting Estimate how many breaks from sitting time periods when people spend sig- or lying in each of these categories you take during 1 hour of sitting in each nificant time being sedentary. throughout the day (not sleeping) of these settings (e.g., standing up, stretching, walking). Put an X that best (hr)    (min) captures the frequency of breaks. Traveling to/from places (e.g., bus/car) 5432 10    At school and work (e.g., class, meet-    5432 10 ings, presentations, work) Watching TV or using other media    5432 10 (e.g., TV, video games) Computer use at home (e.g., home-    5432 10 work, Web searching, email) Other leisure activities (e.g., reading,    5432 10 relaxing, talking) Total Sedentary Time 5 5 _____ hr 1 _____ min Average Break Score 5 _____ 3. Calculate the time spent in light activity by subtracting your estimated sedentary time (step 2) from the estimated time spent in Sedentary 1 Light (step 1). Estimated Light Activity 5 25 Sedentary 1 Light (step 1) Sedentary Time (step 2) Light Time 4. Calculate a ratio of sedentary to light activity by dividing Sedentary Time (step 2) by Light Time (step 3). Use the formula below to make your calculations. Estimated Sedentary/Light Ratio 5   /  5 Sedentary Time (step 2) Light Time (step 3) Sedentary/Light Ratio Based on categories and constructs used in the Workforce Sitting Questionnaire (Chau et al., 2011). 112

Cardiorespiratory Endurance Concept 8 LEARNING OBJECTIVES After completing the study of this Concept, you will be able to: c Describe the different components of the cardiovascular and respiratory systems. c List the health benefits of cardiorespiratory endurance. c Outline the FIT formula for moderate to vigorous physical activity designed to promote cardiorespiratory endurance. c Identify several methods of determining exercise intensity levels for promoting cardiorespiratory endurance, select the method you think is most useful to you, and explain the reasons for your choice. c Describe key guidelines for monitoring aerobic exercise, including self-monitoring heart rate. c Indicate several self- assessments for cardiorespiratory endurance, select the self-assessment you feel is most useful to you, and explain the reasons for your choice. Cardiorespiratory endurance is probably the most important aspect of physical fitness because it has a major impact on health and greatly influences physical performance. 113

114 Section 3  c  The Physical Activity Pyramid Cardiorespiratory fitness is generally considered to pump and receive blood in a rhythmical fashion to maintain be the most important aspect of physical fitness. good circulation (see Figure 1). Blood containing a high Those who possess reasonable amounts of fitness have a concentration of oxygen is pumped by the left ventricle decreased risk for heart disease, reduced risk for prema- through the aorta (a major artery), where it is carried to the ture death, and improved quality of life. Regular aerobic tissues. Blood flows through a sequence of arteries to capil- exercise promotes fitness and provides additional health laries and to veins. Veins carry the blood containing lesser and wellness benefits that extend well beyond reducing amounts of oxygen back to the right side of the heart, first risks for disease. This Concept describes the function of to the atrium and then to the ventricle. The right ventricle the cardiovascular system and explains how to determine pumps the blood to the lungs. In the lungs, the blood picks the appropriate intensity of exercise needed to promote car- up oxygen (O2), and carbon dioxide (CO2) is removed. diorespiratory endurance. From the lungs, the oxygenated blood travels back to the heart, first to the left atrium and then to the left ventricle. Elements of Cardiorespiratory The process then repeats itself. A dense network of arter- Endurance ies distributes the oxygenated blood to the muscles, tissues, and organs (see Figure 2). The term cardiorespiratory endurance has several synonyms. Cardiorespiratory endurance is the ability of Healthy arteries are elastic, are free of obstruction, and the heart, blood vessels, blood, and respiratory system to expand to permit the flow of blood. Muscle layers line the supply nutrients and oxygen to the muscles, and the ability arteries and control the size of the arterial opening upon the of the muscles to utilize fuel to allow sustained exercise. A impulse from nerve fibers. Unfit arteries may have a reduced person with good cardiorespiratory endurance can persist in internal diameter (atherosclerosis) because of deposits on physical activity for relatively long periods without undue the interior of their walls, or they may have hardened, non- stress. Cardiorespiratory endurance is the preferred name elastic walls (arteriosclerosis). for this component of fitness, but it is sometimes referred to as cardiovascular fitness, cardiovascular endurance, or The blood in the four chambers of the heart does not aerobic fitness. The lab measure of this component of fit- directly nourish the heart. Rather, numerous small arteries ness is referred to as aerobic capacity (discussed later in within the heart muscle provide for coronary circulation. this Concept). Field tests such as those Poor coronary circulation precipitated by unhealthy arteries in Lab 8B measure cardiorespiratory can be the cause of a heart attack. endurance, but scores are sometimes used to estimate aerobic capacity. VIDEO 1 Deoxygenated blood flows back to the heart through a series of veins. The veins are intertwined in the skeletal Good cardiorespiratory endurance requires a fit heart muscle, and this allows normal muscle action to facilitate muscle. The heart is a powerful muscle that pumps blood the return of blood to the heart. When a muscle is con- through the body. The heart of a normal individual beats tracted, the vein is squeezed, and this pushes the blood reflexively about 40 million times a year. In a single day, the back to the heart. Small valves in the veins prevent the heart pumps over 4,000 gallons of blood through the body. backward flow of the blood, but defects in the valves can To keep the cardiovascular system working effectively, it is lead to pooling of blood in the veins. A common condition, crucial to have a strong and fit heart. known as varicose veins, is associated with the pooling of blood in the leg. Regular physical activity helps reduce Like other muscles in the body, the heart becomes stron- pooling of blood in the veins and helps keep the valves of ger if it is exercised. The size and strength of the heart the veins healthy. increases, and it can pump more blood with each beat, accomplishing the same amount of work with fewer beats. Capillaries are the transfer stations where oxygen and fuel Typical resting heart rate (RHR) values are around 70–80 are released, and waste products, such as carbon dioxide, are beats per minute, but a highly trained endurance athlete may removed from the tissues. The veins receive the blood from have a resting heart rate in the 40s or 50s. There is some the capillaries for the return trip to the heart. individual variability in RHR, but a decrease in your RHR Good cardiorespiratory endurance requires healthy with training indicates clear improvements in cardiorespira- blood and a fit respiratory system. The process of tak- tory endurance. ing in oxygen (through the mouth and nose) and delivering Good cardiorespiratory endurance requires a fit it to the lungs, where it is picked up by the blood, is called vascular system. The heart has four chambers, which external respiration. External respiration requires fit lungs as well as blood with adequate hemoglobin. Hemoglobin carries oxygen through the bloodstream. Lack of hemoglo- bin reduces oxygen-carrying capacity—a condition known as anemia.

Concept 8  c  Cardiorespiratory Endurance   115 Tissue cells Superior vena cava CO2 Pulmonary Lung capillaries artery Systemic O2mPuol-n- capillaries ary vein CO2 CO2 Alveolus O2 O2 Lung Right atrium Systemic O2 Left atrium Pulmonary valve capillaries Bicuspid valve Tricuspid valve CO2 Aortic valve Inferior vena cava Left ventricle Right ventricle Aorta Tissue cells Figure 1  c  Cardiovascular and respiratory systems. Delivering oxygen to the tissues from the blood is called (see Table 1). Breathing rate and depth increase, allowing internal respiration. Internal respiration requires an adequate the body to take in more oxygen. The heart beats faster and number of healthy capillaries. In addition to delivering oxy- pumps more blood with each beat (increased stroke vol- gen to the tissues, these systems remove carbon dioxide. ume). The higher heart rate and larger stroke volume allow Good cardiorespiratory endurance requires fitness of both more blood to be pumped each minute (increased car- the external and internal respiratory systems. diac output). During exercise, the blood passing through the lungs picks up more oxygen and distributes it more Cardiorespiratory endurance requires fit muscle quickly. Activation of the sympathetic nervous system also tissue capable of using oxygen. Once the oxygen is leads to a redistribution of the blood flow, so that more delivered, the muscle tissues must be able to use oxygen of it gets shunted to the working skeletal muscle. Dur- to sustain physical performance (see Figure 2e). Physi- ing rest, the muscles get about 20 percent of the available cal activity that promotes cardiorespiratory endurance blood flow, but this increases to about 70 percent during stimulates changes in muscle fibers that make them more vigorous exercise. Within the muscles, a larger percentage effective in using oxygen. Outstanding distance runners have high numbers of well-conditioned muscle fibers Aerobic Capacity The ability to supply oxygen during very that can readily use oxygen to produce energy for sus- (vVi˙g  Oor2omusaxp)h.ysical activity typically measured by a laboratory test tained running. Training in other activities would elicit Hemoglobin  The oxygen-carrying protein (molecule) of red similar adaptations in the specific muscles used in those blood cells. activities. Anemia  A condition in which hemoglobin and the blood’s oxygen-carrying capacity are below normal. During exercise the performance and function of the cardiovascular and respiratory systems are maximized. During exercise, a number of changes occur to increase the availability of oxygen to the muscles

116 Section 3  c  The Physical Activity Pyramid Major Blood Vessels Cardiorespiratory Endurance Characteristics Carotid Open, healthy Figure 2a. A Fit Heart artery coronary arteries • Strong ventricles Subclavian Strong, thick • Open coronary vessels vein heart muscle • Good collateral circulation Subclavian artery Figure 2b. A Fit Respiratory Aorta System and Healthy Blood Heart • Good capillaries Vena • Healthy blood with ample cava hemoglobin Iliac artery • Open coronary vessels Iliac vein Figure 2c. Healthy Arteries Femoral vein • Elastic Femoral artery • Large diameter • No obstructions Intima • No atherosclerosis Media (Muscle) Adventitia Figure 2d. Healthy Veins and Intima Valves Media • Thinner, less elastic walls Adventitia • Large diameter • Good valves Muscle Figure 2e. Fit Muscles Tendons • Good artery supply • Efficient at using oxygen to produce energy Figure 2  c  Major blood vessels and cardiorespiratory endurance characteristics.

Concept 8  c  Cardiorespiratory Endurance   117 Table 1  c  Changes in Cardiovascular and Adaptations to regular aerobic exercise result in Respiratory Function Between Rest and Exercise for improved cardiorespiratory endurance. Specific adap- a Person with Good Cardiorespiratory Endurance tations occur within each of the systems shown in Figure 2. The heart muscle gets stronger and pumps more blood with Rest Maximal each beat, allowing the heart to pump less frequently to Exercise deliver the same amount of oxygen. The lungs and blood Lungs Breathing Rate (breaths/min) 12 function more efficiently in picking up oxygen and deliver- 30 ing it to the muscles. The vessels more effectively deliver the Heart Heart Rate (beats/min) 70 190–200 blood and the muscles adapt to use oxygen more efficiently. These adaptations allow a person to take in and use more Stroke Volume (mL/beat) 75 150 oxygen during maximal exercise (increased aerobic capac- 28.5 ity or V˙ O2 max). The adaptations contribute to improved Cardiac Outputa (L/min) 5.2 70% endurance performance as well as health benefits. 20% Arteries Blood Flow Distribution (%) 20% 60 Muscle Oxygen Extraction (%) 5% Cardiorespiratory Endurance and Health Benefits System V˙  O2 (mL/kg/min)b 3.5 Good cardiorespiratory endurance reduces risk for aCardiac output 5 heart rate 3 stroke volume. heart disease, other hypokinetic conditions, and bV˙  O2 5 oxygen consumption 5 CO 3 oxygen extraction. early death. Numerous studies over the past 30 to 40 years have confirmed that good cardiorespiratory endurance is of the available oxygen is also extracted from the muscles associated with a reduced risk for heart disease as well as during exercise. Collectively, these changes help provide a number of other chronic, hypokinetic conditions. The the muscles with the oxygen needed to maintain aerobic consensus is that low-fit individuals are three to six times metabolism. more likely to develop symptoms of heart disease, meta- bolic syndrome, or diabetes than high-fit individuals. While Aerobic capacity is evaluated using an indicator the specific amount of fitness needed to reduce risks varies or V˙ O2 max. A by condition and population, evidence clearly supports the known as maximum oxygen uptake, max), commonly need for at least a moderate level of fitness. As shown in person’s maximum oxygen uptake (V˙ O2 Figure 3, there are dramatic reductions in risk in moving referred to as aerobic capacity, is determined in a laboratory from the low fitness category to the moderate fitness cat- by measuring how much oxygen a person can use in maxi- egory for both males and females. In terms of longevity, mal exercise. The test is usually done on a treadmill using studies suggest that individuals with moderate fitness will specialized gas analyzers to measure live 5–6 years longer than low-fit individuals. High-fit indi- oxygen use. The treadmill speed and viduals have the lowest risk, but as the principle of dimin- grade are gradually increased, and ishing returns indicates, the drop in risk from moderate to when the exercise becomes very hard, VIDEO 2 high fitness is not as great as the drop in risk from low to moderate fitness. oxygen use reaches its maximum. The test is a good indicator of the ability of the cardiovascular and respiratory systems to function effectively. Elite endurance athletes can extract 5 or 6 liters of oxy- gen per minute from the environment, and this high aero- The benefits of cardiorespiratory fitness are bic capacity is what allows them to maintain high speeds in both training and competition without becoming excessively independent of its beneficial effect on other risk factors. Physical activity has been tired. In comparison, an average person typically extracts shown to have beneficial effects on about 2 to 3 liters per minute. V˙ O2 max is typically adjusted some other established heart disease to account for a person’s body size because bigger people risk factors, such as cholesterol, blood VIDEO 3 may have higher scores due to their larger size. Values are reported in milliliters (mL) of oxygen (O2) per kilogram (kg) of body weight per minute (mL/kg/min). The field tests in Lab 8B assess your cardiorespiratory endurance. They are functional fitness tests that determine Maximum Oxygen CUopmtamkoen(lVy˙  Oref2ermreadx)t oAaslaVb˙o  Ora2tomryaxm, eoarsuthree your ability to persist in exercise for relatively long periods of aerobic capacity. volume (V) of oxygen used when a person reaches his or her of time. Some, such as the Bicycle Test, allow you to esti- maximum (max) ability to supply it during exercise. mate your aerobic capacity (V˙ O2 max).

118 Section 3  c  The Physical Activity Pyramid High cannot be fit if they are overweight or overfat. It is now known that appropriate physical activity can build cardio- Hypokinetic disease risk and Males respiratory endurance in all types of people, including those risk for early death Females with excess body fat. In fact, numerous studies have dem- onstrated that a fit, overweight person is at lower risk of Low chronic disease than an unfit person who is normal weight. Low fitness Moderate fitness High fitness These findings demonstrate that for chronic disease pre- vention, low fitness is a greater risk than excess body fat- Figure 3  c  Risk reduction associated with cardiorespiratory ness. The greatest risk is among people who are both unfit endurance. and overfat. Source: Adapted from Blair et al. Good cardiorespiratory endurance enhances the ability to perform various tasks, improves the ability pressure, and body fat. It is important to note that the benefi- to function, and is associated with a feeling of cial effects of cardiorespiratory endurance on risk for heart well-being. Moving out of the low fitness zone is of obvi- disease and early death are considered to be independent of ous importance to disease risk reduction. Achieving the these other effects. This means that active/fit people would good zone on tests further reduces disease and early death still have lower health risks even if their cholesterol, blood risk and provides wellness benefits, including the ability pressure, and body fat levels were identical to those in a to enjoy leisure activities and meet emergency situations. matched set of inactive/unfit people. This evidence contrib- In older adults, achievement of good fitness results in an uted to the labeling of physical inactivity as a major, inde- improved ability to function and maintain independence. pendent risk factor for heart disease. The risk associated Cardiorespiratory endurance in the high-performance zone with physical inactivity is as large as (or larger than) risks provides benefits that may be important for success in cer- associated with any of the other established risk factors. tain athletic events and in occupations that require high per- formance levels (e.g., firefighters). Good fitness reduces risks for normal weight, overweight, and obese people. Some people think they The FIT Formula for Cardiorespiratory Endurance HELP Health is available to Everyone for a Lifetime, and it’s Personal The FIT formula for cardiorespiratory endurance College students have some unique opportunities to be varies for people of different activity levels. Adap- active on campus. Most students have easy access to a tations to physical activity are based on the overload well-equipped recreation center and the ability to enroll in principle and the principle of progression. It is important various intramural programs. Building physical activity into to provide an appropriate challenge to the cardiovascu- your routine in college can help you sustain or develop lar and respiratory systems (overload), but the challenge an active identity, even if you weren’t previously active in should be progressive, increasing gradually as fitness sports or exercise. Finding time to exercise now can also improves. For most people, vigor- help you make similar adjustments to changing obliga- ous physical activity from steps 2 tions and priorities later in life. and 3 (see Figure 4) is necessary How have your physical activity patterns changed since to improve cardiorespiratory endur- VIDEO 4 you entered college? Do you take advantage of campus opportunities to be active? How confident are you that ance. However, for people with low you will be able to be physically active later in life? fitness, moderate physical activity (step 1) produces improvements. Table 2 presents the FIT ACTIVITY formulas for people of five different fitness and activity levels. While the frequency of exercise is similar for the different levels, the intensity and amount of time spent in activity vary considerably. The sections that follow pro- vide added information about the FIT formula. The frequency (F) of physical activity to build cardiorespiratory endurance ranges from 3 to 5 or more days a week. The ACSM guidelines for build- ing cardiorespiratory endurance suggest a frequency of at least 5 days a week for low-fit people who do primarily

Concept 8  c  Cardiorespiratory Endurance   119 moderate physical activity. Moderate activity can be safely The intensity (I) of physical activity necessary to performed every day and can provide additional benefits. For more active people (and those with higher levels of produce cardiorespiratory endurance depends on a person’s level of fitness. Consistent with the over- cardiorespiratory endurance), vigorous physical activ- load principle and the principle of progression, you need ity at least 3 days a week is recommended. Vigorous physical activity provides Energy Balance additional benefits (com- Energy Out Energy In pared to moderate activity); (Activity) (Diet) however, it can increase risk for orthopedic injury if it is done too frequently. Therefore, 5 days a week is the maximal recommended STEP 5 Flexibility • Yoga Exercises • Stretch dose for most people. Healthy people who are fit and regularly active and STEP 4 Muscle • Calisthenics have no evidence of joint Fitness • Resistance Exercises exercise problems or injuries may train up to 6 days a week, but most experts agree that Vigorous Sports • Tennis at least 1 day off a week STEP 3 and Recreation • Hike is beneficial. Use Table 2 to determine the appropri- ate frequency of exercise STEP 2 Vigorous • Jog Aerobics • Bike • Aerobic dance for you based on your cur- rent activity and fitness level. Complete the fitness assessments at the end of STEP 1 Moderate • Walk this Concept before making Physical Activity • Yard work • Golf your decision. The ACSM guidelines focus on exercise for building cardiorespira- tory endurance but are simi- Avoid Inactivity lar to national guidelines Figure 4  c  Select activities from steps 2 and 3 of the pyramid for optimal cardiorespiratory designed to produce health endurance. and wellness benefits. Source: C. B. Corbin. Table 2  c  FIT Formula for Cardiorespiratory Endurance for People of Different Fitness and Activity Levels Fitness Level Very Low Low Marginal Good High Performance Activity Level Sedentary Some light to Sporadic moderate Regular moderate to Habitual moderate F 5 Frequency (days per week) moderate activity to vigorous activity vigorous activity to vigorous activity I 5 Intensity   Heart Rate Reserve (HRR) 3–5 3–5 3–5 3–5 3–5   Max. Heart Rate (maxHR)   Relative Perceived Exertion (RPE) 30–40% 40–55% 55–70% 65–80% 70–85% T 5 Time (minutes per day) 57–67% 64–74% 74–84% 80–91% 84–94% 12–13 12–13 13–14 13–15 14–16 20–30 30–60 30–90 30–90 30–90

120 Section 3  c  The Physical Activity Pyramid to exercise at a gradually increasing level of intensity that Different patterns of activity can be used to achieve is higher than normal to improve cardiorespiratory endur- the recommended dose of exercise. Some people may ance. To determine the appropriate intensity, it is important prefer to perform regular 30-minute bouts of exercise but to have some indicator of a person’s overall fitness. If the others may prefer to accumulate it throughout the day. A maximal aerobic capacity is known, an appropriate intensity pattern of three 10-minute bouts provides similar benefits to can be set at a percentage of the maximum level. Because one 30-minute session. The number of days per week can these values cannot be calculated without special equip- vary from 3 to 6 days per week, but exercising one day a ment, other indicators of relative intensity are more com- week with no regular activity in between (i.e., being a week- monly used. end warrior) is discouraged. The prescriptions in Table 2 are aimed at improving cardiorespiratory endurance based on Heart rate provides a good indicator of the relative chal- individual characteristics of typical people. Specialized train- lenge presented by a given bout of exercise. Therefore, ing regimens are typically needed for guidelines for the intensity of physical activity to build those interested in high-performance cardiorespiratory endurance are typically based on percent- events (e.g., running races, triathlons) ages of heart rate reserve (HRR) or maximal heart rate and competitive sports. VIDEO 5 (maxHR). Current guidelines as outlined in Table 2 specify different intensity levels based on current fitness and activity Threshold and Target Zones levels. Calculations of HRR and maxHR will be described for Intensity of Activity to Build in detail later, but the general range for HRR is 30 to 85 per- Cardiorespiratory Endurance cent and for maxHR, 57 to 94 percent. There is a minimum intensity and an optimal Ratings of perceived exertion (RPE) refer to the intensity range for activity designed to develop assessment of the intensity of exercise based on how the cardiorespiratory endurance. As noted earlier, moni- participant feels; a subjective assessment of effort. RPE toring heart rate and making ratings of perceived exertion has been shown to be useful in assessing the intensity are the most practical methods of determining the intensity of aerobic physical activity. The RPE scale ranges from of activity necessary to build cardiorespiratory endurance. 6 (very, very light) to 20 (very, very hard), with 1-point The threshold of training (minimum intensity) and the tar- increments in between. If the values are multiplied by 10, get zone (optimal intensity range) can be determined using the RPE values loosely correspond to HR values (e.g., several methods. Most methods are based on heart rate so 60  5  rest HR and 200  5  maxHR). Details will be pro- the target zone is typically referred to as target heart rate vided later, but the target zone for aerobic activity is from zone. Ratings of perceived exertion (RPE) can also be used 12 to 16 (see Table 2). to define the target zone for exercise intensity. This section provides details of using these methods. Regardless of what method is used, the important point is that lower intensities provide a cardiorespiratory endurance An estimate of maximal heart rate (maxHR) is needed benefit for low-fit sedentary people, but higher intensities to determine appropriate target heart rate zones are needed for more fit people. Use Table 2 to determine the for aerobic exercise. Your maxHR is the highest heart appropriate intensity of exercise based on your current activ- ity and fitness level. Aerobic activities provide an ideal stimulus for improving cardiorespiratory endurance. The amount of time (T) for building cardiorespiratory endurance is typically based on minutes of activity per day. The ACSM, the American Heart Association, and the U.S. Department of Health and Human Services all recommend a minimum of 150 minutes of moderate activity per week, or 75 minutes of vigorous activity per week (or a combination of minutes from moderate and vigorous activity). Extending the length of time for exer- cise bouts has additional benefits for health and wellness, as well as cardiorespiratory endurance. For example, 150 to 300 minutes of moderate activity per week is beneficial in losing body fat and maintaining a healthy body weight. For fit and active people, extending bouts of vigorous activity from 20 up to 90 minutes provides health and wellness benefits and enhances cardiorespiratory endur- ance. Use Table 2 to determine the appropriate length of time for daily exercise for you based on your current activ- ity and fitness level.

Concept 8  c  Cardiorespiratory Endurance   121 A CLOSER LOOK Online Fitness Tools and Calculators calculators vary considerably in the values produced as well as in the terms used to describe the target zones. Search “Target Keeping up with fitness terminology and recommendations can Heart Rate Calculator” online to see how they vary. be challenging, but it is especially difficult when you get differ- ent information from different sources. For example, many peo- Do you find these types of online calculators and resources ple have misconceptions about exercise heart rate calculations. helpful? Target heart zones should take into account your age and your resting heart rate as well as existing fitness level, but Web-based ACTIVITY rate attained in maximal exercise. It could be determined (maxHR  5  206  3  [.88  3  age]). There is currently no using an electrocardiogram while exercising to exhaus- consensus on the most accurate method, but evidence sup- tion; however, it can also be estimated with formulas. ports the utility of a relatively simple nonlinear method MaxHR is known to decrease with age so one simple and known as the Tanaka formula: maxHR 5 208 2 (.7 3 age). commonly used approach is to subtract your age from Calculations made at a variety of ages show little, if any, 220 (i.e., maxHR  5  220  2  age). However, studies have differences between the formulas, so it is recommended for shown that this formula leads to inaccurate estimates for most applications. Table 3 illustrates the calculations for most people. A number of more specialized, nonlinear determining maxHR for a 22-year-old. equations have been developed to avoid this problem. For The heart rate reserve (HRR) method is the preferred example, a new formula for women was recently developed way to calculate target heart rate zones. Table 2 pro- vides five different intensity ranges for activity designed to Table 3  c  Sample Target Heart Zone Calculations build cardiorespiratory endurance. After you have assessed for a 22-Year-Old, Using the Percentage of Heart your fitness using fitness tests (see Lab Resource Materials Rate Reserve Method and Lab 8B), determine which of the five intensity ranges is best for you based on your current activity and fitness. Calculating Maximal Heart Rate Table 3 provides a worked example for calculating heart rate target zones using the HRR method. The example is for Maximal heart rate 5 208 2 (.7 3 age) a 22-year-old with good cardiorespiratory endurance who 5 208 2 (.7 3 22) does regular moderate-to-vigorous physical activity and 5 208 2 15.4 who has a resting heart rate of 68 beats per minute. The target heart rate zone for this hypothetical person is 65 to 193 80 percent. Calculating Heart Rate Reserve To determine the threshold of training (minimum heart rate for building cardiorespiratory endurance), use Maximal heart rate 193 bpm 65 percent of the working heart rate, and then add that Minus resting heart rate 2 68 bpm value to the resting heart rate. To determine the upper limit Equals heart rate reserve (HRR) of the target zone, use 80 percent of the working heart rate 125 bpm and add that value to the resting heart rate. Because tar- get zone heart rates vary for people of different fitness and Calculating Threshold Heart Rate activity levels and because resting and maximal heart rates HRR 125 bpm Heart Rate Reserve (HRR) The difference between maximal 3 65% 3 .65 heart rate (highest heart rate in vigorous activity) and resting Equals heart rate (lowest heart rate at rest). Plus resting heart rate 81 bpm Ratings of Perceived Exertion (RPE)  The assessment of the Equals threshold heart rate 168 bpm intensity of exercise based on how the participant feels; a subjec- tive assessment of effort. 149 bpm Calculating Upper Limit Heart Rate HRR 125 bpm 3 80% 3 .80 Equals 100 bpm Plus resting heart rate 168 bpm Equals upper limit heart rate 168 bpm

122 Section 3  c  The Physical Activity Pyramid E ect of Age and Resting Heart Rate on Target Heart Range Rest HR Threshold 20 25 30 35 40 45 50 55 60 65 50 65% 144 141 139 137 135 132 130 128 125 123 80% 165 162 160 157 154 151 148 146 143 140 55 65% 145 143 141 139 136 134 132 129 127 125 80% 166 163 161 158 155 152 149 147 144 141 60 65% 147 145 143 140 138 136 133 131 129 127 80% 167 164 162 159 156 153 150 148 145 142 65 65% 149 147 144 142 140 137 135 133 131 128 80% 168 165 163 160 157 154 151 149 146 143 70 65% 151 148 146 144 142 139 137 135 132 130 80% 169 166 164 161 158 155 152 150 147 144 75 65% 152 150 148 146 143 141 139 136 134 132 80% 170 167 165 162 159 156 153 151 148 145 Figure 5  c  Effect of age and resting heart rate on target heart range. vary, each person will have a unique range of heart rates performs regular moderate-to-vigorous activity, the percent- defining the target heart rate zone. The chart in Figure 5 ages would be 80 to 91 percent. The maxHR for our hypothet- allows you to look up similar threshold and target heart ical 22-year-old is 193, so the target heart rate zone would be rate zones based on your resting heart rate and age (up to 154 to 176 using this method (.80 3 193 5 154 and .91 3  age 65). Locate your resting heart rate on the left and your 193 5 176). As illustrated in Table 3, this procedure yields age across the top. The values at the point where they inter- somewhat similar but higher values for the maxHR method sect represent your target heart rate (based on 65 percent than for the HRR method. The differences between the two and 80 percent of HR reserve). Look across the columns methods vary for people of different ages, resting heart rates, for a given row to see how the target zone changes with and fitness/activity levels. The percentage of maxHR method age. Look down the rows for a certain column and see how is considered an acceptable alternative method, but the HRR the target zone changes with fitness. The chart shows that method is more precise. Threshold and target zone heart rates fit individuals (lower rest HR values) have lower target should be used as general guidelines for aerobic exercise. heart rate zones than unfit individuals (higher rest HR val- You should check your resting heart rate and learn to calcu- ues). This may seem somewhat paradoxical but the reason late your target heart range based on the HRR method. It is is that fit individuals start exercise with a lower HR value important to understand how to make the calculations, since and therefore have a larger HRR. the process explains the relationships. The percentage of maximal heart rate method is an The target heart ranges should be used as just that, a gen- alternative way to calculate target heart rate zones. eral target to try for during your exercise session. By bring- The percentage of maxHR method is simpler to use than the ing your heart rate above the threshold and into the target HRR method, but it is not as accurate. This procedure takes zone, you will provide an optimal challenge to your cardio- maximal heart rate into account but does not factor in indi- vascular and respiratory systems and maintain/improve your vidual differences in resting heart rate. People with a typical cardiorespiratory endurance. Guidelines for heart rate moni- resting HR of 60 to 70 bpm will tend to get similar values toring are provided in the next section. with both methods, but the percentage of maxHR method Ratings of perceived exertion can be used to monitor tends to be less accurate for people with high or low resting the intensity of physical activity. The ACSM suggests heart rates. that regularly active people can use RPE to determine if they are exercising in the target zone (see Table 4). Ratings of To use the percentage of maxHR method, first find your perceived exertion have been shown to correlate well with maximum HR with the formula (maxHR 5 208 2 [.7 3 age]). HRR. For this reason, RPE can be used to estimate exer- Then multiply your maxHR by the appropriate percent- cise intensity, avoiding the need to stop and count heart rate ages from Table 2. For a person with good fitness and who

Concept 8  c  Cardiorespiratory Endurance   123 Table 4  c  Ratings of Perceived Exertion (RPE) Rating Description Figure 6  c  Counting your radial (wrist) pulse. 6 Very, very light 7 Very light Figure 7  c  Counting your carotid (neck) pulse. 8 Fairly light the artery. Counting the pulse with the thumb is not recom- 9 Somewhat hard mended because the thumb has a relatively strong pulse of 10 Hard its own, and it could be confusing when counting another 11 Very hard person’s pulse. 12 Very, very hard Counting heart rates during exercise presents some 13 additional challenges. To obtain accurate exercise heart 14 rate values, it is best to count heart beats or pulses while 15 moving; however, this is difficult during most activities. 16 17 The most practical method is to count the pulse imme- 18 diately after exercise. During physical activity, the heart 19 rate increases, but immediately after exercise, it begins to 20 slow and return to normal. In fact, the heart rate has already slowed considerably within 1 minute after activity ceases. Source: Data from Borg. Therefore, you must locate the pulse quickly and count the during exercise. A rating of 12 is equal to threshold, and a rating of 16 is equal to the upper limit of the target zone. With practice, most people can recognize when they are in the target zone using ratings of perceived exertion. Guidelines for Heart Rate and Exercise Monitoring Learning to count heart rate can help you monitor the intensity of your physical activity. Each time your heart beats, it pumps blood into the arteries. The surge of blood causes a pulse, which can be felt by holding a finger against an artery. The major arteries that are easy to locate and are frequently used for pulse counts are the radial, just below the base of the thumb on the wrist (see Figure 6), and the carotid, on either side of the Adam’s apple (see Figure 7). Count- ing the pulse at the carotid is the most popular procedure, probably because VIDEO 6 the carotid pulse is easy to locate. The radial pulse is a bit harder to find because of the many tendons near the wrist, but it works better for some people. To count the pulse rate, simply place the fingertips (index and middle finger) over the artery at the wrist or neck loca- tion. Move the fingers around until a strong pulse can be felt. Press gently so as not to cut off the blood flow through

124 Section 3  c  The Physical Activity Pyramid In the News Running for Your Health benefit. Perhaps most important is that even short bouts of running (5–10 minutes) have health benefits. (See link in Sug- Each of the activities in the physical activity gested Resources and Readings.) pyramid offers health benefits; however, research indicates that people who run are especially likely to Do these positive results from running increase your interest get health benefits. Runners have a 45 percent lower risk of in incorporating vigorous activity into your physical activity death from heart disease or stroke and a 30 percent lower risk program? Why or why not? of early death. Runners, on average, live 3 years longer than nonrunners. Those who run for 6 years or more get the most ACTIVITY rate for a short period in order to obtain accurate results. For Everyone should learn to determine resting heart rate accu- best results, keep moving while quickly locating the pulse; rately and to estimate exercise heart rate by quickly and then stop and take a 15-second count. Multiply the number accurately making pulse counts after activity (see Lab 8A). of pulses by 4 to convert heart rate to beats per minute. Declines in resting heart rate and exercise heart rate You can also count the pulse for 10 seconds and multiply signal improvements in cardiorespiratory endurance. by 6, or count the pulse for 6 seconds and multiply by 10 to As described in this Concept, the heart beats to provide the estimate a 1-minute heart rate. The latter method allows you body (and working muscles) with oxygen. Oxygen is used to calculate heart rates easily by adding 0 to the 6-second to produce energy using aerobic metabolism. During rest, count. However, short-duration pulse counts increase the the heart can beat relatively slowly to provide sufficient chance of error because a miscount of 1 beat is multiplied by oxygen to the body. During exercise, the demand for energy 6 or 10 beats rather than by 4 beats. increases, so the body increases heart rate (and respiration) to help distribute more oxygen to the body. Changes in rest- The pulse rate should be counted after regular activity, ing heart rate and exercise heart rate provide good indicators not after a sudden burst. Some runners sprint the last few of improvements in fitness because they indicate that the yards of their daily run and then count their pulse. Such a heart can pump fewer times to provide the same amount of burst of exercise will elevate the heart rate considerably. blood flow to the body. A fit individual has a stronger heart This gives a false picture of the actual exercise heart rate. and can pump more blood with each beat. TECHNOLOGY UPDATE A comparison of resting and exercise heart rates for three hypothetical individuals performing the same bout E-bikes of exercise is shown in Figure 8. The column labeled “A” The electric bike (e-bike) is a new type of bicycle designed Heart rate 200 A B C to promote active commuting. The e-bike has a small elec- 180 Exercise tric engine that provides assistance to the rider only when 160 Low Fit Mod Fit Resting pedaling, providing speeds up to about 15 mph. The e-bike 140 90 70 was developed in Switzerland to encourage people who 120 160 130 High Fit live in hilly terrain to ride bicycles. A recent study showed 100 17 14 50 that the effort necessary to ride an e-bike to work (about 80 100 6 METs) was less than the effort needed to ride a regular 60 11 bike. Most of the commuters in the study were easily able 40 to use the bike to commute to work. The e-bike is gaining 20 popularity in other countries because it is comfortable and practical and contributes to cleaner air. The e-bike also 0 encourages otherwise inactive people to become active. Rest HR Would you consider using an e-bike as a way to get more HR active and help the environment? RPE ACTIVITY Figure 8  c  Comparison of resting and exercise heart for three 22-year-old individuals (maxHR 5 193) with different levels of fitness (A 5 low fitness, B 5 moderate fitness, C 5 high fitness).

Concept 8  c  Cardiorespiratory Endurance   125 shows the response of an unfit person. This person has a to the results for a moderately fit (B) or highly fit (C) per- high resting heart rate of 90, and this increases to 160 dur- son. Both have a lower resting heart rate and a lower exer- ing the exercise. This intensity would feel pretty hard, so cise heart rate, so exercise is easier and can be maintained an RPE would likely be about 17. Compare this response more easily. Strategies for Action An important first step in developing properly. It does allow you to estimate your aerobic capacity (V˙ O2 max). The swim test is especially useful to those with mus- and maintaining cardiorespiratory culoskeletal problems and other disabilities. The running test is the most vigorous and for this reason may be best for more endurance is assessing your current status. For an activ- advanced exercisers with high levels of motivation. ity program to be most effective, it should be based on per- Results on the walking, running, and swimming tests are greatly influenced by the motivation of the test taker. If the test sonal needs. Some type of testing is necessary to determine taker does not try hard, fitness results are underestimated. The bicycle and step tests are influenced less by motivation your personal need for cardiorespiratory endurance. The best because one must exercise at a specified workload and at a measure is a laboratory assessment of V˙ O2 max, but this is not regular pace. Because heart rate can be influenced by emo- possible for most people. To provide alternatives, researchers tional factors, by exercise prior to the test, and other factors, tests using heart rate can sometimes give incorrect results. have developed other tests that give Thus, do your self-assessments when you are relatively free from stress and are rested. reasonable estimates. Commonly used Prior to performing any of these tests, be sure that you tests are the step test, the swim test, are physically and medically ready. Prepare yourself by doing some regular physical activity for 3 to 6 weeks before actually the 12-minute run, the Astrand-Ryhming VIDEO 7 taking the tests. If possible, take more than one test and use the summary of your test results to make a final assessment of bicycle test, and the walking test. These your cardiorespiratory endurance. In Lab 8B, you will have the opportunity to self-assess your cardiorespiratory endurance tests are developed based on compari- using one or more tests. A non-exercise estimate of cardiore- sons with measured V˙ O2 max and are good general indicators spiratory endurance is also provided for comparison. Although of cardiorespiratory endurance. In Lab 8B you will be able to this self-report tool has limitations, it is increasingly being used as a screening tool in physicians’ offices to determine if compare estimates from several tests. patients have risks associated with poor fitness. The self-assessment you choose depends on your current fitness and activity levels, the availability of equipment, and other factors. The walking test is probably best for those at beginning levels because more vigorous forms of activity may cause discomfort and discourage future participation. The step test is somewhat less vigorous than the running test and takes only a few minutes to complete. The bicycle test is also sub- maximal or relatively moderate in intensity. It is quite accurate but requires more equipment and expertise than the other tests. You may need help from a fitness expert to do this test ACTIVITY Suggested Resources ∙ Duck-chul, L., et al. (2014). Leisure-time running reduces all- and Readings cause and cardiovascular mortality risk. Journal of the American College of Cardiology, 64(5): 472–481. The websites for the following sources can be accessed by searching ∙ Eckel, R. H., et al. (2013). 2013 AHA/ACC guideline on life- style management to reduce cardiovascular risk. Circulation, 129 online for the organization, program, or title listed. Specific scientific (suppl. 2): S76–S99. references are available at the end of this edition of Concepts of Fit- ∙∙ Huffington Post: The Real Danger of “Too Much Exercise.” ness and Wellness. Lee, J., et al. (2014). Track it: Validity and utility of consumer- ∙ ACSM. (2014). ACSM’s Guidelines for Exercise Testing and based physical activity monitors. ACSM’s Health and Fitness Prescription (9th ed.). Philadelphia: Lippincott, Williams & Wilkins. Journal, 18(4): 16–21. ∙ American Heart Association: Recommendations for Physical Activity in Adults. ∙ PubMed Health: Running 7 Minutes a Day Halves Health Risk. Bushman, B. A. (2014). Determining the I (intensity) for a ∙ FITT-VP aerobic exercise prescription. ACSM’s Health and Fitness Journal, 18(3): 4–7.



Lab Resource Materials:  Evaluating Cardiorespiratory Endurance Lab Resource Materials Evaluating Cardiorespiratory Endurance The Walking Test The Step Test • Warm up; then walk 1 mile as fast as you can without • Step up and down on a 12-inch bench for 3 minutes at straining. Record your time to the nearest second. a rate of 24 steps per minute. One step consists of four beats—that is, “up with the left foot, up with the right • Immediately after the walk, count your heart rate for foot, down with the left foot, down with the right foot.” 15 seconds; then multiply by four to get a 1-minute • Immediately after the exercise, sit down on the bench heart rate. Record your heart rate. and relax. Don’t talk. • Use your walking time and your postexercise heart • Locate your pulse or have someone locate it for you. rate to determine your rating using Chart 1. • Five seconds after the exercise ends, begin counting Chart 1  Walking Ratings for Males and Females your pulse. Count the pulse for 60 seconds. 170+ • Your score is your 60-second heart rate. Locate your score and your rating on Chart 2. 160 Chart 2  Step Test Rating Chart 150 Classification 60-Second Heart Rate Heart rate (bpm) 140 Low High-performance zone 84 or less zone 130 Good fitness zone Marginal Good fitness zone 85–95 zone 120 Marginal zone 96–119 Low zone 120 and above 11014 15 16 17 18 19 20 21 Source: Kasch and Boyer. or less Time (min) or more Females As you grow older, you will want to continue to score well on this rating chart. Because your maximal heart rate decreases as you age, you should be able to score well if you exercise regularly. 170+ The Astrand-Ryhming Bicycle Test 160 • Ride a stationary bicycle ergometer for 6 minutes at Heart rate (bpm) 150 Low a rate of 50 pedal cycles per minute (one push with zone each foot per cycle). Cool down after the test. 140 Marginal • Set the bicycle at a workload between 300 and 1,200 130 zone Good fitness zone kpm. For less fit or smaller people, a setting in the range of 300 to 600 is appropriate. Larger or fitter 120 people will need to use a setting of 750 to 1,200. The workload should be enough to elevate the heart rate 110 13 14 15 16 17 18 19 to at least 125 bpm but no more than 170 bpm during 12 Time (min) or more the ride. The ideal range is 140–150 bpm. or less Males • During the sixth minute of the ride (if the heart rate is Source: James M. Rippe, M.D. in the correct range—see previous step), count the The ratings in Chart 1 are for ages 20 to 29. They provide reasonable heart rate for the entire sixth minute. The carotid or ratings for people of all ages. radial pulse may be used. Note: The walking test is not a good indicator of high performance; the • Use Chart 3 (males) or 4 (females) to determine your running and bicycle tests are recommended. predicted oxygen uptake score in liters per minute. Locate your heart rate for the sixth minute of the ride in the left column and the work rate in kp · m/min across the top. The number in the chart where the heart rate and work rate intersect represents your predicted O2 uptake in liters per minute. The bicycle you use must allow you to easily and accurately determine the work rate in kp · m/min. 127