Paediatric Exercise Physiology

350 PAEDIATRIC EXERCISE PHYSIOLOGY End-diastolic volume The volume of blood contained within the heart at the end of diastole. Endomorphy The classification of physique that assesses the degree of roundness, or fatness. End-systolic volume The volume of blood remaining in the heart at the end of contraction. Enzyme A protein with specific catalytic activity. Almost all metabolic reactions are dependent on and controlled by enzymes. Error/residual The numerical value of the distance of an individual data point from a regression prediction line. Error is positive when the point falls above the line and negative when below. Estimation paradigm A passive process by which the individual provides a rating of perceived exertion in response to a request from the investigator to indicate how ‘hard’ the exercise feels at that moment in time. This information may then be used to compare responses between conditions after some form of intervention or to assist in the prescription of exercise intensity. Estimation–production paradigm In the estimation–production paradigm, expected or derived values of objective intensity measures derived from a previous estimation trial are compared to values produced during a subsequent exercise trial(s) in which the child actively self-regulates exercise intensity levels using predetermined RPEs. Explanatory variable Any independent variable entered into a multilevel regression model, e.g. stature, mass, age etc. Fatigue index (FI) An indicator of fatigue given by the difference between the highest and the lowest power achieved, expressed as a percentage of the highest power output. Forced expiratory volume in 1 second (FEV1) The volume exhaled during the first second of a forced expiratory manoeuvre. Forced vital capacity (FVC) The volume of air exhaled during a forced maximal expiration following a forced maximal inspiration. 40% Δ. Forty per cent of the difference between ventilatory threshold and peak VO2. Functional residual capacity (FRC) The lung volume after a normal expiration. Gain Oxygen cost relative to the stimulus (exercise intensity). Gluconeogenesis The synthesis of glucose from non-carbohydrate precursors such as glycerol and amino acids.

Glossary 351 Glycogenolysis The breakdown of glycogen into glucose 1-phosphate by the action of phosphorylase. Glycolysis The anaerobic degradation of one molecule of glucose to two molecules of pyruvate. Growth Changes in size of an individual, as a whole or in parts. Haematocrit Volume of red cells usually expressed as a percentage of total blood volume. Heat capacity The quantity of heat needed to produce a unit rise of temperature in the body and measured in J · °K–1. Heteroscedasticity Describes the spread in data around a regression line where the error term increases as the magnitude of the dependent variable increases. Hot environment Air temperature as high as 40–50°C. High-density lipoproteins (HDL) HDLs transport cholesterol from the tissues to the liver to be broken down and excreted. HDLs accelerate the clearance of cholesterol from the blood, reducing the likelihood of cholesterol becoming deposited in arterial walls to cause arteriosclerosis, and thereby reducing the risk of coronary heart disease. Hydrolysis A reaction in which large molecules are split by interaction with water into smaller molecules. Hyperpnoea Excessive ventilation due to an increase in breathing frequency and/or tidal volume. Independent variable Variable on the Y axis (vertical axis) of a bivariate plot. Inotropic effect Altered force of contraction in heart rate muscle normally due to autonomic nervous system stimulation or inhibition. Intima media thickness Thickness of the intima media of the artery, which can be seen as an indicator of preclinical atherosclerosis. Lactate threshold (TLAC) The point at which blood lactate accumulation increases non-linearly in response to progressive exercise. Linear regression equation Y = a + bX + ε. Lipolysis The breakdown of triacylglycerols (triglycerides) into fatty acids and glycerol. Lipoproteins Organic compounds formed from lipids and proteins that transport fats and cholesterol in the blood.

352 PAEDIATRIC EXERCISE PHYSIOLOGY Logarithm, natural Obtained by multiplying a number by a factor known as Euler’s constant (e = approximately 2.71828). Log-likelihood (i.e. –2*log-likelihood) Sometimes called the deviance statistic. Used to judge the goodness of fit of nested multilevel regression models. Log-linear regression equation The linear form of the allometric equation: loge Y = loge a + b · loge X + loge ε. Longitudinal research Studies in which data are obtained on the same individual three or more times during a period of time. Low-density lipoproteins (LDL) LDLs transport cholesterol to all non-hepatic cells. Excess cholesterol tends to be deposited on the blood vessel wall and is associated with the development of arteriosclerosis. Maturation Process of being mature, or the progress towards the mature state. Maximal intensity exercise The performance of any type of exercise that requires an all-out effort and where the predominant, though not exclusive, energy supply for the accomplishment of the exercise is from anaerobic metabolism. Maximal lactate steady state (MLSS) The highest exercise intensity that can be maintained without incurring a progressive increase in blood lactate. It reflects the highest point at which the diffusion of lactate into the blood and removal from the blood are in equilibrium. . Maximal oxygen uptake (VO2max) The highest rate at which an individual can consume oxygen during exercise. Maximal voluntary ventilation (MVV) Measurement of air exhaled over a period of time, usually 15 s, expressed in L · min–1 BTPS. Mean power (MP) The average power output achieved during maximal intensity exercise lasting between 1 and 60 s. MP is usually averaged over 30 s. Mean.response time (MRT) Time from the onset of exercise to reach 63% of the final VO2 amplitude; equal to the sum of the delay time and time constant in an exponential model that incorporates a delay. Mesomorphy The classification of physique that assesses the degree of muscularity, and bone development. Metabolic syndrome Having three or more risk factors for CVD. . Minute ventilation (VE) The volume of air taken in or breathed out in 1 minute, usually expressed in L · min–1 BTPS. Multilevel modelling An extension of multiple regression analysis appropriate for analysing multilevel or hierarchically structured data such as longitudinal growth and exercise data.

Glossary 353 Multiplicative error Allometric models assume multiplicative error, i.e. the magnitude of the error term increases as the range of values measured for the dependent and independent variables increase (i.e. demonstrate heteroscedasticity). Muscle action The state of the muscle that is dependent upon the external force applied to that muscle. Muscle moment arm Perpendicular distance from the axis of rotation to the line of action of the intrinsic muscle force. Normoxia Normal levels of oxygen. OMNI Scale A 0–10 perceived exertion scale which depicts four characters at various stages of fatigue on a 20–25° incline. The scale is anchored with six equally distributed verbal descriptors along the scale, which utilize various states of feeling ‘tired’. Ontogenetic allometry Allometric body size and exercise performance relationships examined at the individual level. Optimized peak power (PPopt) The highest power output obtained from force- velocity tests that involve a number of sprints lasting 5–10 s against a range of applied resistances. Osmolality The number of particles per kilogram of solvent. Osteopenia The state prior to the disease state of osteoporosis. Osteoporosis A condition characterized by enhanced skeletal fragility. Oxygen deficit The difference between the theoretical oxygen requirement and the volume of oxygen actually used during a period of exercise in which the level of oxygen uptake is insufficient to supply the energy required. . Peak oxygen uptake (peak VO2) The highest oxygen uptake observed during an exercise test to exhaustion. Peak post-exercise lactate The highest lactate concentration achieved during or shortly after an exercise protocol. Peak power (PP) The highest power output achieved during maximal intensity exercise lasting between 1 and 60 s. PP is usually averaged over 1, 3 or 5 s. Perceived exertion The sensation of strain, aches and fatigue from the peripheral muscles and pulmonary system, among other sensory cues. This is mediated by the interplay of three main effort continua – perceptual, physiological and performance environment. Perceptual continuum The initial basis from which to explore the derivations of the ratings of perceived exertion. It is founded on the premise that perception plays

354 PAEDIATRIC EXERCISE PHYSIOLOGY a fundamental role in our behaviour and in how we adapt to a situation. It involves factors such as mood, understanding and motivation. Performance/situational continuum The interplay of the perceptual continua and the unique patterns of physiological responses on the RPE are influenced by the situational characteristics of the performance. pH A measure of the relative acidity or alkalinity of a solution. A pH of 7 indicates neutrality, values above 7 indicate alkalinity, and those below 7 indicate acidity. . Phase 1 Also termed the cardiodynamic phase. The initial increase in VO2 following the onset of exercise that is due to an increase in pulmonary blood flow and pulmonary ventilation. . Phase 2 The exponential increase in VO2 following the onset of exercise and phase 1. Represents oxygen uptake dynamics at the muscle, also termed the primary component. . Phase 3 The VO2 following the achievement of the asymptote of the exponential in phase 2. Physiological continuum Perceived exertion is related to heart rate, blood lactate, oxygen uptake, respiratory frequency, ventilatory volume and body temperature, among other factors. Some factors are characterized by linear growth of increases in intensity (e.g. heart rate) and some factors are characterized by a non-linear (positive accelerating) growth function. Pictorial Children’s Effort Rating Table (P-CERT) The scale depicts a child running up a 45° stepped gradient at five stages of exertion, corresponding to CERT ratings of 2, 4, 6, 8 and 10. All the verbal descriptors from the original CERT are included in the scale. Pneumotachograph A device used to measure gas flow by measuring the pressure drop across a tube with known resistance to flow. Poikilothermal Having a varying body temperature. Population attributable risk (PAR) A risk estimate that combines the prevalence of the risk factor with the relative risk for the risk factor for a certain health outcome. Power function ratio The ratio Y/Xb where b is the slope of the log-linear relationship. Preload The end-diastolic volume at the beginning of systole. Primary component See Phase 2. Production paradigm An active process in which the individual is required to actively produce an intensity based upon his/her interpretation of effort sense and the cognition and understanding of the RPE prescribed.

Glossary 355 Production-only or repeat-production paradigm The assessment of perceived exertion using a repeat-production paradigm examines a child’s ability to discern between different target RPEs while self-regulating exercise intensity on more than one occasion. Proximal The segment of the body closest to the centre of the body; opposite of distal. Ratio standard The variable constructed when a measure of physiological function is divided by body mass, e.g. mL · kg–1 · min–1, W · kg–1, etc. Residual volume (RV) The volume of gas remaining in the lung at the end of a maximal expiration. Respiratory exchange ratio (R) The ratio of the volume of carbon dioxide expired per minute to the volume of oxygen consumed during the same time in the lungs. Saltation Increase in the size of the body through unique time-constrained episodes that occur intermittently. Scaling The process of removing or controlling for the influence of body size upon physiological function. Shortening fraction (SF) The difference between the diameter of the ventricles at the end of systole (ESD) and the original diameter at the end of diastole (EDD), expressed as a percentage (SF = (EDD – ESD)/EDD). Simple linear equation (Y = bX + ε) The mathematical model assumed when the ratio standard is applied. This equation represents a straight line that passes from zero through the intersection of the mean values for the Y and X variables. Slow component Increase in oxygen uptake during phase 3 above the oxygen uptake predicted from the linear power–oxygen uptake relationship below the anaerobic threshold. Somatotyping The method of defining a person’s body type or physique in terms of classifications of ectomorphic, endomorphic and mesomorphic components. Specific latent heat of vaporization The quantity of heat required to change a unit mass of a substance from liquid to vapour without a change in temperature and measured in J · g–1. Static muscle actions Muscle generates force whilst remaining at a fixed length. Statis No measurable accretion in growth, or increase in size occurs; separates individual saltation events. Stroke index The expression of stroke volume in relation to body surface area (mL · m–2). Stroke volume The amount of blood ejected from one ventricle per heartbeat (mL).

356 PAEDIATRIC EXERCISE PHYSIOLOGY Syndrome X The clustering of dyslipidaemia, hypertension, hyperinsulinaemia and obesity. t1/2 Half-time of the response. The time taken to achieve 50% of the total change in the response. Testosterone Circulating hormone that is responsible for the stimulation of the anabolic process of skeletal muscle growth. The deadly quartet Another name for the clustering of dyslipidaemia, hypertension, hyperinsulinaemia and obesity. Thermal strain The physiological and mental response to thermal stress. Thermal stress An accumulation of environmental conditions that stress the thermoregulatory system. Thermoneutral zone The temperature range where mammals do not have to use extra energy to conserve or dissipate heat. Tidal volume (VT) The volume of air that is inhaled or exhaled with each respiratory cycle. Time constant (τ) Time taken to reach 63% of the final amplitude of an exponential function. Torque A product of the muscle force and the muscle moment arm. Total lung capacity (TLC) The volume of gas contained in the lung after a full inhalation. Tracking Predictability of values measured at an early age for values of the same variable later in life. Tricarboxylic acid cycle A series of chemical reactions occurring in the mitochondria in which carbon dioxide is produced and hydrogen and electrons are removed from carbon molecules. During the cycle energy is liberated and used to synthesize ATP from ADP and Pi. Turbine flow meter A device used to measure gas flow by measuring the number of revolutions of a rotating turbine per unit of time. Velocity The rate of change of position and direction over time, calculated by dividing distance by time. Venous return The amount of blood that enters the heart from the venous circulation. Ventilatory threshold (TVENT) Point in an incremental exercise test at which ventilation increases disproportionately to oxygen uptake.

Glossary 357 Very low-density lipoproteins (VLDL) VLDLs transport triglycerides synthesized in the liver to the adipose tissue. VLDL residuals may become LDLs associated with the development of coronary heart disease. Vital capacity (VC) The volume change that occurs between maximal inspiration and maximal expiration. Warm environment Air temperature up to 8–10°C above skin temperature, ~30–40°C. Wind chill An index that quantifies the effect of cold upon the skin as well as overall heat loss. Wind chill is directly related to the velocity of the wind.

359 Index Notes Aδ fibres, 241 Page numbers in italics refer to figures and Adolescence tables. Page numbers in bold refer to glossary entries. growth spurt see Growth spurt(s) puberty see Puberty A Adrenal hormones maturity, indicators of, 19 Accelerometry, 176 see also specific hormones Acclimation, 253, 261–2, 347 Adrenaline Acclimatization, 261–2, 263–5, 347 cardiac contractility, 141 Accretion, 2 phosphorylase activity enhancement, 79 Accumulated oxygen deficit (AOD) Adrenarche, 19 Adult height see Stature, adult test, 103–4 Aerobic energy sources, 72, 74 heritability index, 112 Aerobic fitness/power, 161–87 limitations, 104 anaerobic fitness knowledge versus, Acetylcholine (ACh), 141, 142 Acetyl coenzyme A (acetyl CoA), 78, 80, 82 99–100, 100 Acetylene rebreathing, 144 blood lactate see Blood lactate Acidosis, lactate build-up and, 78 definition, 162, 347 Actin, 48, 49 growth/maturation and, 74 Active paradigm, perceived exertion, maximal see Maximal oxygen uptake 277–8 (VO2max) Actomyosin, 49 peak oxygen uptake see Peak oxygen Acute macrotrauma, 317–18 Additive error, 347 uptake (peak VO2) Adenosine diphosphate (ADP), 75–6 performance in athletes, 309–10 Adenosine monophosphate (AMP), 75–6 secular trends, 178–9 Adenosine triphosphate (ATP) trainability, 157 see also Aerobic training anaerobic metabolism response to Aerobic training training, 229 age-related susceptibility to, 310 characteristics, 223 exercise metabolism, 75–6 effects in athletes, 309–10 glucose catabolism, yield from, 81, 82 response, 222–7, 230–1 hydrolysis, 76 intramuscular stores, 76 baseline influence, 225, 225–6 lipid metabolism, 83 blunted response, 224 muscle mechanism, 49 golden period, 223–4, 231 oxidative carbohydrate metabolism, 80 intensity effects, 226–7 oxygen uptake and, 162 sex differences, 227 resting stores, 85 Afterload, 141, 150, 347 resynthesis, 76, 77, 79, 92 Age at peak height velocity (APHV) see Peak height velocity (PHV), age at Airway, 121, 135

360 INDEX Aldolase, 78 Androgens, 223 Aldosterone, 262 Anorexia nervosa, 315, 347 Allometric equation, 347 Anthropometric measurement Allometric scaling/modelling techniques, 49 body size and cardiac function, 146–7 Antidiuretic hormone (ADH), 244 body size and peak oxygen uptake, Aorta diameter estimation, 145 Arterial carbon dioxide concentration 170–1, 171 cross-sectional studies, 29, 34–7, 35–8, 43 (CaCO2) measurement, 143–4 muscle strength, 56 Arterial partial pressure of carbon dioxide ontogenetic see Ontogenetic allometry power data, 110 (PaCO2), 124, 125, 132 Alveolar ventilation, optimum (VA), 129 Arterial partial pressure of oxygen (PaO2), Alveoli, 121 Amenorrhoea, 315–16, 316 124, 132 bone mineral density and, 317 Arterial remodelling, 333 definition, 347 Arteriovenous oxygen difference, 175, 347 primary, 315 Atherosclerosis, 332, 333 secondary, 315–16 Athlete see Young athlete American Academy of Pediatrics, 262, 311 Athlete triad see Female athlete triad American College of Sports Medicine, 262, Athletics 326, 329 age-related records, 72, 72, 73 American football players, 308, 319, 320–1 menarche, age at, 306 Amsterdam Growth and Health peak height velocity, 309 Atlas matching, Greulich-Pyle technique, Longitudinal Study (AGAHLS), 330–1 10–11 body fatness, 334, 335 ATPases, 75–6 cardiovascular disease, 332–3 Atrioventricular node (AV node), 142 metabolic syndrome, 336 Australian Sports Medicine Federation, 262 Anaerobic capacity, 28, 208–9 Auxology see Growth; Maturation/ Anaerobic energy sources, 72, 74 Anaerobic fitness maturity aerobic fitness knowledge versus, ‘Awareness of effort,’ 278 99–100, 100 Axillary hair, 17, 18 age-related differences, 107–8, 108, 110–11, 111 B athletes, 310–11 definition, 100, 347 Bainbridge reflex, 152 determinants of, 111–13 Ballet dancers development, 107–11 cross-sectional studies, 107–10, body composition, 304 108, 109 body mass, 304 longitudinal studies, 110–11, 111 maturity status, 307 sex differences in, 109–10 sports injury in, 318–19 longitudinal studies, 110–11, 111 stature, 302 training response, 227–30 Basal metabolic rate (BMR), heart rate anaerobic metabolism, 229–30, 231 short-term power output, 228–9 association, 149 Anaerobic metabolism, training response, Baseball, 308 229–30, 231 Basketball, 301–2, 309 Anaerobic threshold (TAN), 191, 193, β-oxidation, 82 197–9, 347 b exponent (mass exponent), 348 Anaerobic-to-aerobic power ratio, 74–5, 75 Biacromial (shoulder) breadth, 9, 348 Analysis of covariance (ANCOVA), 29, Bicristal (hip) breadth, 9, 348 32–3, 347 Biological maturity see Maturation/ Anatomical cross-sectional area (ACSA), resistance training, 218, 219, 220 maturity Biopsy, 348 muscle, 84, 94, 229, 230 Blood flow during exercise, 242–3 Blood glucose, 335–6 Blood haemoglobin concentration, 174–5

Index 361 Blood lactate, 78, 87, 179–83 training influence, 304 age-related changes, 87 velocity curve, 7, 8 assay, 180–1, 181 Body mass-for-age curve, 7, 8 assessment, 180–1, 181 Body mass index (BMI), 335 exercise, response to, 182, 182–3 Body position age-related changes, 182–3, 183 cardiac output and, 149 maturation effect, 182–3 heart rate effect, 148 sex differences, 182–3 stroke volume effect, 147–8, 150, 150 interpretation of, 179–80 Body proportions, 3–5, 4, 9 oxygen uptake kinetics and, 206–7 Body size post-exercise concentration cardiovascular function and, 146–7 duration of test effects, 107 maturity-associated variation, 21–2 heritability index, 112 muscle strength development and, longitudinal studies, 110 maximal intensity exercise, 106–7 59–60 mode of test effects, 107 peak oxygen uptake and, 169–70, 171 peak oxygen uptake determination, performance interpretation and, 164, 165–6 variation in, 180 27–46 reference values, 181–2, 182 see also specific study designs sampling, 180 sport selection, 311–12 terminology, 180 Body surface area (BSA) thresholds, 181–2, 182 body mass ratio, heat loss, 259, 261 training response, 229 cardiac function and, 147 stroke volume and, 146 Blood osmolarity, thirst trigger, 269 temperature regulation and, 243 Blood pressure, cardiovascular disease Body temperature acclimatization/acclimation, 262 and, 332–3 balance see Heat balance Blood vessel constriction, 241, 259 cardiac drift, 155 Blood volume, stroke volume and, 141 control see Thermoregulation Body composition core, stability, 240 high, symptoms/consequences, 244, athletes, 304–5 245–6 cardiovascular disease, 334–5 skin temperature, 240 Body dimensions Body temperature and pressure, saturated exercise test to exhaustion and, 127 (BTPS), 348 growth, 3–5, 4 Body water, 7, 266 Body fat/fatness, 7 Body weight preoccupation, 314–15 athletes, 304, 305 Bone hypertrophy, 339 cardiovascular disease, 334–5 Bone mass dietary intake, 341 athletes, 304 measurement/interpretation, 335 lifestyle factors, 337–8 sex differences, 9, 174 peak, 317, 337 see also Obesity see also Bone mineral density (BMD) Body fluid see Fluid balance Bone mineral density (BMD) Body function, maturity-associated amenorrhoea and, 317 asymmetrical, tennis players, 304 variation, 21–2 impact loading and, 317 Body mass osteoporosis, 316 physical activity and, 338, 338–9 anaerobic fitness and, 110 see also Bone mass diurnal variation, 7 ‘Bone specific scoring,’ Tanner-Whitehouse growth and, 7–9, 8, 27–8 technique, 10–11 muscle strength development and, Boxing, 319 Brainstem respiratory centre, 132 59, 59–60 Breasts, development of, 16, 17 peak oxygen uptake and see Peak Breath-by-breath, 348 oxygen uptake (peak VO2), body mass and peak velocity, 7 sex differences, 7–9, 8

362 INDEX Breathing frequency (fR), 122–3, 127–9, 128 body fatness, 334–5 definition, 348 diabetes and, 335–6 response to metabolic demand, 124 lipoproteins, 331–2 tidal volume ratio, 127–9 metabolic syndrome, 336–7, 337 ‘new’ risk factors, 333 Bronchial system, 121 physical activity in childhood and, 329 Bug and Bag Effort (BABE) Scale, 284–6, 285 risk factor tracking, 341 Bulimia nervosa, 315, 348 Cardiovascular drift, 154–5, 155 Cardiovascular function, 139–60 C body size and, 146–7 cardiac output see Cardiac output (Q) Calcium, muscle mechanism, 49 exercise, during, 150–7 Calf muscle exercise, treadle ergometer, heart rate see Heart rate (HR) maximal, sex differences, 175 90–1 at rest, 147–9 Canoeing, 306 stroke volume see Stroke volume Carbohydrate training effects, 157–8, 309–10 Cardiovascular Risk in Young Finns Study, metabolism, 80–1, 81, 82 muscle storage, 76 333, 336, 340 Carbohydrate-electrolyte drinks, 268, 268 Carnitine palmitoyl transferase, 86 Carbon dioxide (CO2) Cart and Load Effort Rating (CALER) arterial concentration (CaCO2), 143–4 arterial partial pressure (PaCO2), 124, Scale, 283–4, 284 definition, 348 125, 132 heart rate and, 285, 286 elimination, 124 reliability, 284–6, 286 end-tidal partial pressure (PETCO2), validation, 286 CATCH study, 333 125, 131 Catecholamines production (VCO2), 123 cardiac contractility effect, 152 cardiovascular disease and, 332 kinetics of, 130 oxidative metabolism and, 80 measurement, 143–4 response to exercise, 88–9 rebreathing, 143–4 stroke volume and, 152–3 Cardiac index (CI), 146, 147 see also specific types age-related changes, 149, 157 Centers for Disease Control and definition, 348 maximal, 157 Prevention, 329 sex differences, 149 Centile, 348 Cardiac output (Q), 140, 140–2 C fibres, 241 age-related changes, 149, 156–7 Chemoreceptors, 132–3 body position effects, 149 Children’s Effort Rating Table (CERT), body size and, 146 see also Cardiac index (CI) 279, 279–80 definition, 140, 348 definition, 348 exercise, response to, 156–7 derivation of, 280–2, 281, 282 heat balance and, 242–3 heart rate and, 280, 282–3 maximal, 156–7 pictorial versions, 279–80, 283–8, 284–7 measurement, 142–6 invasive methods, 142–3 validation, 289–90 non-invasive methods, 143–6 see also Pictorial Children’s Effort see also specific methods Rating Table (P-CERT) peak oxygen uptake and, 169, 203 power output and, 282–3 at rest, 149 reliability, 284–5 sex differences, 149, 157 support for a 1–10 scale, 282–3 trainability of, 157 validation, 280–2, 281, 282, 292 variability in, 149 Children’s Health and Exercise Research Cardiovascular disease, 331–7 Centre, 165 blood pressure, 332–3 Cholesterol levels, 342 body composition, 334–5 see also specific types

Index 363 Chronological age ratio scaling of, 32, 32 definition, 348 perceived exertion scales, 285, 286 skeletal age versus, 11 Cycling, 309, 319 talent identification, 312–14 Cycling peak power (CPP) age-related changes, 74, 108, 109 Chronotropic effect, 348 definition, 349 Citrate, 80 determination, 73–4 Citrate synthase (CS), 86 Climate, relative age effect, 312 see also Wingate anaerobic test Clothing (WAnT) inertial load force–velocity test, 103 exercise in a hot environment, 262, 266 recovery from, 113–14 heat absorption/reflection, 239 sex differences, 74 Cold environment, 259–61, 260, 348 Cold receptors, 241 D Colon cancer, 326 Competition stress, 306 Dalhousie Leg Fatigue Scale, 291, 291 Compliance, 348 Dance, 319 Computerized tomography (CT), 50 Concussion, 320 ballet see Ballet dancers Conduction, 236, 237, 242, 259 Dead space (VDS), 129, 349 Contact sports, injuries, 320–1 Dehydration Continuous exercise, perceived exertion, definition, 349 293–5, 294 heat and, 244 Contractility, cardiac, 141, 151–2 mechanism of, 267 Contusions, 320 studies, 267–8 Convection, 236, 238, 242, 259 thirst correlation, 269 Cool environment, 348 Delay time (δ), 349 Cooling mechanism, 237 Dependent variable, 349 Core body temperature stability, 240 Development, definition, 2, 349 Coronary heart disease, 326 Diabetes mellitus, 326, 335–6 Cortisol, 80 Dietary intake recommendation, 340–1 Creatine kinase (CK), 76, 86 Dieting, 314 Critical power (CP), 198–9, 349 Differentiated rating of perceived exertion Critical weight–critical fat hypothesis, 307 Cross-bridge formation, 49 (RPE), 349 Cross-sectional studies see also Rating of perceived exertion anaerobic fitness development, 107–10, (RPE) 108, 109 Dihydrotestosterone, 20 Dimensionality theory, 37–8 definition, 3, 349 Direct Fick method, 142–3 interpretation, 28–38 Disease prevention, 326 Disordered eating, 314–15 allometric scaling, 29, 34–7, 35–8, 43 Distal, definition, 349 linear regression scaling, 29, 32–4, Distance runners, 304, 307 33–5, 43 Distensibility, 349 ratio scaling, 28–32, 29–31, 43 Diurnal variation theoretical exponents, 37–8 peak oxygen uptake and maturation, 172 body mass, 7 pulmonary adaptation to training, 134 definition, 349 training response studies, 215 stature, 5 Curvilinear perceived exertion scale, 290, Diving, 306 290–1 Doppler echocardiography, 144–5 Cycle ergometer tests Drinking see Fluid intake maximal intensity exercise, 101–4 Dye dilution method, 143 maximal power training response, 228 Dynamic force assessment, 54 methodology, 104 Dynamic muscle actions, 349 minute ventilation, 125 Dynamometer, 55 oxygen uptake determination, 194 Dyslipidaemia, 336 peak, 164–5

364 INDEX E Environmental factors/temperature, 235–73 Early maturers body size/function, 21 acclimation, 253, 261–2 peak height velocity and, 11 acclimatization, 261–2, 263–5 fluid balance, 266–70, 267, 268 Eating disorders, 314–15 growth/maturation influence, 20 Ectomorphy, 305–6, 349 heat see Heat Effort low temperature, physiological estimation and production, 277–8 response to, 259–61, 260 perception anchoring, 292 Enzymes, 85–6, 350 Ergometers, 164–5 see also Perceived exertion Effort continua, 276, 276–7, 349 see also specific types Ejection fraction (EF), 152, 349 Error term (ε), 33–4, 350 Elbow extensors, 63 Essential hypertension, 332–3 Elbow flexors Estimation paradigm, 350 Estimation-production paradigm, 293, 350 isokinetic strength, 63 Eston–Parfitt curvilinear perceived isometric strength, 57 exertion scale, 290, 290–1 body mass association, 59, 59–60 European Pediatric Work Physiology muscle cross-sectional area and, 62 Conference (1997), 288 resistance training, 218 Evaporation, 236, 237–8 motor unit activation %, 66 Exercise Electrically evoked muscle stimulation, 52–3 blood lactate response, 182, 182–3 muscle contractile capacity cardiac output response, 156–7 measurement, 65–6 cardiovascular function and, 150–7 supramaximal, 65 fluid balance and, 266 tetanic, 65–6 heart rate response, 154–6 Electrolyte concentration, 244, 256–8 intensity Electromagnetic energy wave radiation, 238–9 acclimatization/acclimation Electronically evoked twitch, 349 programme, 262 Electron transport chain (ETC), 80, 83 aerobic fitness response to training, Elite athlete, 300 226–7 see also Young athlete control using ratings of perceived Emotions exertion, 292–3 heart rate effect, 148 minute ventilation elevation, 125, 126 perceived exertion, 276 oxygen uptake kinetics, 191, 191, End-diastolic volume, 153, 350 197–9 Endomorphy, 305, 350 see also specific intensities End-systolic volume, 350 limiting factors, 133–4 End-tidal partial pressure of carbon metabolism, 71–97 dioxide (PETCO2), 125, 131 adenosine triphosphate, 75–6 End-tidal partial pressure of oxygen energy stores, 85 (PETO2), 125 enzyme activity, 85–6 Endurance training glycogenolysis see Glycogenolysis aerobic fitness increase susceptibility, glycolysis see Glycolysis 223–4 hormonal responses, 88–9, 94 age-related differences in response, lactate production, 86–7, 94 223–4 muscle fibre types/characteristics, cardiovascular adaptation, 333 83, 83–4, 84–5 peak oxygen uptake effect, 157 oxidative metabolism see Oxidative pulmonary adaptation, 134 metabolism Energy stores, 85 oxygen uptake kinetics see Oxygen Energy yield, estimations of, 100 uptake kinetics ‘En pointe’ dancing, 319 paediatric, 84–94 31P magnetic resonance spectroscopy, 89–91, 90, 94

Index 365 phosphocreatine, 75–6 Forced expiratory volume in 1 second recovery studies, 93–4, 95 (FEV1), 123, 350 substrate utilization, 88, 94 pulmonary function, 123–34, 133–4 Forced vital capacity (FVC), 123, 350 stroke volume response, 150, 150–4, Force-velocity cycling test (FVT), 102–3 151 thermal responses to, 251 anaerobic fitness, 110 thermoregulation during, 254 limitations, 102–3 see also specific types maximal power training response, 228–9 Exercise-induced arterial hypoxaemia multilevel modelling, 111 (EIAH), 133–4, 135 Fractures, 317, 320 Exercise. -ind.uced ventilation–perfusion Frank–Starling mechanism, 141, 152 (VA/Q) inequality, 133–4 Free fatty acids, 80, 82 Exercise test to exhaustion, 127, 162–3 Fructose 1,6-diphosphate (FDP), 78 Exhaustive effort, signs of, 165 Fructose 6-phosphate, 78 Explanatory variable, 350 Fumarase, 86 Extracellular fluid composition, 266–7 Fumarate, 80 Functional residual capacity (FRC), 122, 122, 350 F G Facial hair, 17, 18 Gain, 350 FADH2, 80 Genetic predisposition theory (two-part Fainting, 245 Fast twitch muscle fibres see Muscle fibre, biocultural hypothesis), 307 Genital growth, 3–4, 4 type IIa (fast twitch - fatigue Genotype, 20 resistant); Muscle fibre, type IIX Globe thermometer, 239 (fast twitch - fatigable) Glucagon, 80 Fat-free mass, 7 Gluconeogenesis, 350 age-related changes, 62 Glucose 1-phosphate (G1P), 76 athletes, 304–5 Glucose 6-phosphate (G6P), 76, 78, 229 muscle strength development and, Glucose degradation, 76 61–2 Glycaemic control, physical activity Fatigue index (FI), 101, 112, 350 Fatigue resistance, 93–4 and, 335 Fatty acyl CoA, 82 Glycerol, 82 Fatty acyl CoA synthase, 82 Glycogen Female athlete triad, 314–17 amenorrhoea, 315–16, 316 breakdown see Glycogenolysis disordered eating, 314–15 liver storage, 85 osteoporosis, 316–17 muscle storage, 76 Fetal muscle development, 48 Fick principle, 142–3, 143–4, 169 age-related changes, 85 Field tests, muscle strength, 56 training response, 229 Figure skating, 302, 304, 306 Glycogenolysis Flavin adenine dinucleotide (FAD), 80 definition, 76, 351 Fluid balance, 266–70, 267, 268 exercise metabolism, 76–9, 77 sweating effects, 244 regulation, 79 see also Dehydration; Fluid intake Glycolysis Fluid intake definition, 76, 351 drink desirability, 268 exercise metabolism, 76–9, 77 exercise in a hot environment, 262, 266 indicators of, 106–7 strategies, 268–70 regulation, 79 thirst, 268, 269 Glycolytic enzyme activity, 86 Follicle-stimulating hormone (FSH), 20 Gonadal hormones, maturity indicator, 19 Food intake, body fatness and, 334 Gonadotrophic hormones, 20 Greulich-Pyle atlas technique, 10–11 Growth, 1–26, 3–9 athletes, 301–9

366 INDEX Growth—(cont’d) Healthy People 2010, 327 body dimensions/proportions, 3–5, 4 Heart body mass, 7–9, 8 body proportions, 9 mass, sex differences, 153 definition, 2, 351 muscle strength, afterload general, 3, 4, 4 muscle size, resistance training and, 219 determination, 141 patterns, 3–4, 4 size, body size association, 146 canalization, 302 see also entries beginning cardio-/cardiac peak oxygen uptake and, 169–71, 170, Heart rate (HR), 140, 140–2 171, 172 acclimatization/acclimation, 262 physical training effects, 302–3 age-related changes, 148–9, 155–6 rate (velocity), 5–7, 6 body position effects, 148 reference standards/percentiles, 301 cardiac output association, 156 regulation, 19–20 cardiovascular drift, 154–5, 155 ‘spurts’ see Growth spurt(s) Cart and Load Effort Rating (CALER) stature, 5–7, 6 Scale, 285, 286 Growth hormone (GH) Children’s Effort Rating Table (CERT), anaerobic fitness and, 113 cardiovascular disease and, 332 280, 282–3 golden period of training response, 223 deflection point, 154 muscle strength development and, 61 emotional state effect, 148 oxidative metabolism and, 80 exercise, response to, 154–6 maximal (HRmax) Growth spurt(s) adolescent, 4–5, 5 exercise intensity, 165 body mass, 7 exercise test type effect, 155–6 body proportions, 9 rating of perceived exertion and, 278 physical training effect, 303 sex differences, 175 juvenile/mid, 5 regulation mechanism, 154 timing of, 4–5 at rest, 148–9 sex differences, 149, 156 Guanosine diphosphate (GDP), 80 steady state, 154 Guanosine triphosphate (GTP), 80 trainability of, 157 Gymnasts venous return and, 152 Heart rate deflection point (HRDP), 154 body composition, 304 Heat body mass, 304 balance see Heat balance maturity status, 307, 320 capacity, 239, 351 menarche, age at, 306 exercise guidelines, 262, 266 peak height velocity, 309 physiological response to, 242–58, sports injury in, 319, 319–20, 320 245–6, 247–58 stature, 302, 302, 303, 303, 312 strategies in, 262, 266 tolerance, 243, 247, 263 H transfer, 237 Heat-activated sweat glands (HASG), 243 Haematocrit, 351 Heat balance, 236–42 Haemoglobin concentration, blood, 174–5 conduction, 236, 237, 242, 259 Half-relaxation time (HRT) electrical convection, 236, 238, 242, 259 core temperature stability, 240 stimulation, 220–1 evaporation, 236, 237–8 Handball, 306 factors influencing, 236, 236 Handgrip assessment, 54 heat storage, 236, 239–40 Harpenden Growth Study, 51–2 high temperatures see Heat Harvard Alumni Study, 329, 331 metabolism, 236–7 Head injury, 320 radiation, 236, 238–9, 242, 259 Health Education Authority, 327 thermoneutral zone (TNZ), 241 Health, physical activity and see Physical thermoregulation outside the neutral zone, 241–2 activity, health and work, 236, 239

Index 367 Heat cramps, 245 Hypothalamus Heat exhaustion (volume depletion), 245 growth/maturation regulation, 20 Heat injury/illness, 244 temperature regulation and, 240, 241, Heat loss, evaporation, 237 242 Heat retention in newborns/neonates, Hypothermia, 241 241–2 Hypovolaemia, cardiac drift, 155 Heat storage, 236, 239–40 Hypoxia, chemoreceptor response, 132–3 Heat stress reaction, 252 Heatstroke, 245–6 I Heat syncope (fainting), 245 Heavy intensity exercise ICC analysis, 284 Ice hockey, 309, 319, 320 glycolytic activity, 91 Impact loading, bone mineral density oxygen uptake kinetics see Oxygen and, 317 uptake kinetics, heavy exercise Inactivity see Physical inactivity ventilation, minute, 131–2 Incremental exercise tests, blood lactate Height see Stature Height-for-age curve, 5, 6 concentration, 181–2, 182 Height velocity curve, 5, 6 Incubators, 242 Heritability index (HI), 112 Independent variable, 351 Heteroscedasticity, 30, 33–4, 351 Inertial load force–velocity test (iFVT), Hexokinase (HK), 78, 79 High-density lipoproteins (HDL), 103, 108, 109 Inorganic phosphate (Pi), 75–6 331–2, 351 Inorganic phosphate/phosphocreatine High load–low repetition resistance (Pi/PCr) ratio, 89, 90, 91 training, 222 Inosine monophosphate (IMP), 76 Hip (bicristal) breadth, 9, 348 Inotropic effect, 351 Hormones Insulin anaerobic fitness and, 113 oxidative metabolism and, 80 exercise metabolism, 88–9, 94 physical activity and, 335–6 golden period of training response, 223 response to exercise, 88 growth/maturation regulation, 19–20 Integrated electromyographic activity maturity indicators, 19 muscle size, resistance training (iEMG), 219–20 Intermittent exercise, perceived exertion, and, 219 muscle strength development and, 60–1 293–5, 294 see also individual hormones International Consensus Conference on Hot environment, 351 see also entries beginning heat Physical Activity Guidelines for Humidity, 239–40 Adolescents, 326–7 ‘Hunting reflex’, 259 Interpolated twitch technique (ITT), 66 Hydration Interval runs, anaerobic metabolism exercise in a hot environment, 262 response, 230 status, thirst as an indicator, 268 Intima media thickness, 351 see also Dehydration; Fluid balance; Involuntary dehydration, 269 Isocitrate dehydrogenase (ICDH), 86 Fluid intake Isokinetic cycling test, 103 Hydrolysis, 351 Isokinetic monoarticular tests (IMTs), 106 Hyperinsulinaemia, 336 Isokinetic strength, 55 Hyperplasia, 2 Isometric strength, 54, 55 Hyperpnoea, 124–5, 130, 132, 351 Isometric testing, 56 Hypertension, 336 Isometric torque, 64–5 Hyperthermia, 241 Isotonic exercise, 53–4 Hypertrophy, 2 Hyperventilation, 125, 133 J Hyponatraemia, 244 Hypothalamic-pituitary-ovarian (HPO) Juvenile onset diabetes, 335 axis, 315–16, 316

368 INDEX K Linear regression equation, 170, 170, 351 Linear regression scaling (regression Khamis–Roche method, 15 Knee extensors standards) cross-sectional studies, 29, 32–4, 33–5, 43 isokinetic strength, 63 limitations, 33–4 isometric strength, 57 Lipase, 82 Lipid(s) body mass association, 59–60, 59 metabolism, 82–3 resistance training, 218, 219 storage, 82 testosterone association, 61 see also specific types isotonic strength, 60 Lipolysis, 82, 351 motor unit activation %, 66 Lipoproteins, 331–2, 351 Knee flexors Logarithm, natural, 352 isokinetic strength, 63 Log-likelihood, 43, 352 isotonic strength, 60 Log-linear regression equation, 352 Log-linear scaling see Allometric L scaling/modelling Lacerations, 320 Longitudinal studies Lactate, 78 anaerobic fitness, 110–11, 111 age-related changes, 94 definition, 3, 352 anaerobic metabolism response to interpretation of, 39–43 training, 229 multilevel modelling, 40, 40–3, 42, 44 blood see Blood lactate ontogenetic allometry, 39–40, 40, 43–4 muscle build-up, 78, 93, 103 theoretical exponent application, 39 muscle fibre types and, 84 muscle strength development, 60 production, exercise metabolism, oxygen uptake kinetics in heavy exercise, 205 86–7, 94 peak oxygen uptake, 167–9, 168, 172–3 Lactate dehydrogenase (LDH), 78, 86 physical activity and health, 330–1 Lactate/pyruvate ratio, 87 training response studies, 215 Lactate threshold (TLAC), 87, 181–2 pulmonary adaptation, 134 Low-density lipoproteins (LDL), 331–2, 352 definition, 351 Low temperature, physiological response exercise intensity domains, 92, 191, to, 259–61, 260 Lung(s) 197–8 elasticity, 121–2, 122 range, 182–3 functional residual capacity, 122, 122 Late maturers function measures, 123, 134–5 body size/function, 21 inflation/deflation, 121 familial tendency, 307 sex differences, 134–5 peak height velocity and, 11 size, 134 training effects, 307 structure and mechanics, 120 Latent heat of vaporization, 237, 355 volume, 121, 122, 122, 123 Law of Laplace, 152 see also Pulmonary function Law of the conservation of energy, 236 Luteal deficiency, 315 Lean body mass (LBM) Luteinizing hormone (LH), 20 athletes, 304–5 Lymphoid growth, 3, 4, 4 mean power and, 43 sex differences, 175 M Least squares regression, 32, 33 Left ventricle Magnetic resonance imaging (MRI), body size association, 146 50, 51, 52 mass, 148, 153–4 Left ventricular end-diastolic diameter Magnetic resonance spectroscopy (MRS), 84 anaerobic fitness, 112 (LVEDD), 146 exercise metabolism, 89–91, 90, 94 Leg fatigue scale, 291, 291 Leg length, 5 Levels of agreement (LoA) analysis, 284 Lifestyles, 340–1

Index 369 limitations, 89 Maximal power (Pmax) mechanism, 89 age-related changes, 108 Malate, 80 training response, 228 Martial arts, 319 Maturation/maturity, 1–26 Maximal strength testing, 221 aerobic fitness and, 183, 183, 310 Maximal voluntary ventilation (MVV), anaerobic fitness and, 110 athletes, 306, 306–8, 309, 312, 313 123, 127, 352 blood lactate response to exercise and, Maximal work test (watt-max test), 179 Mean power (MP) 182–3, 183 controlling for, 9–19, 10 age-related changes, 74, 108–9 definition, 352 importance of, 22, 23 determination, 74 definition, 2, 352 heritability index, 112 early see Early maturers lean body mass and, 43 exercise metabolism effects, 91 longitudinal studies, 42–3, 110–11 indicators, 10–19 multilevel regression analyses for, late see Late maturers peak height velocity and, 11 41–2, 42 peak oxygen uptake and, 21–2, 168, non-motorized treadmill test, 104–5 sex differences, 42, 74, 109–10 172–3, 173, 174 training response, 228 rate, 9, 10 Wingate anaerobic test, 101, 102, regulation, 19–20 sport selection, 312, 313 108–9, 110 stages, 2 Mean response time (MRT), 352 tempo, 2, 19, 306 Mechanical loading, bone mineral timing, 2, 306 Maximal aerobic exercise, 100 density, 338–9 Maximal exercise, 100 Medicine and Science in Sports and Exercise, Maximal force, 53, 54 Maximal intensity exercise, 99–117 289 age-related changes, 113–14 Memory, perceived exertion, 276, 277, 292 anaerobic fitness see Anaerobic fitness Menarche, 15–16 cycle ergometer tests, 101–4 age at, 17, 18 see also specific tests assessment methods, 15–16 definition, 100, 352 in young athletes, 306, 306–8 future research, 115 genetic factors, 112 delayed, 315 isokinetic monoarticular tests (IMTs), 106 peak height velocity and, 16 non-motorized treadmill (NMT) test, Meniscal injuries, 320 Mental health, physical activity and, 339 104–6, 105 Mesomorphy, 305–6, 352 post-exercise blood lactate Metabolic demand, minute ventilation concentration, 106–7 response, 124, 124–9 recovery from, 113–14 ‘Metabolic non-specialists’, 72 sex differences, 114 Metabolic syndrome, 336–7, 337, 352 Maximal lactate steady state (MLSS) Metabolism, heat balance, 236–7 definition, 87, 182, 352 Microtraumas, 339 heavy exercise domain and, 92 Minute ventilation (VE) range, 183 Maximal minute ventilation (VEmax), age-related changes, 125 breathing frequency, 127–9, 128 127, 134 definition, 352 Maximal oxygen uptake (VO2max) exercise intensity and, 125, 126 kinetics of, 129–30 definition, 162, 352 peak oxygen uptake versus, 162–3, age-related changes, 130–1, 131 phases, 130 163, 164 sex differences, 131 training adaptation, 134, 222–3 maximal ventilation, 127, 134 see also Peak oxygen uptake (peak VO2) peak oxygen uptake, at, 169 response to metabolic demand, 124, 124–9 tidal volume, 127–9, 128

370 INDEX Minute ventilation (VE)—(cont’d) size ventilatory threshold see Ventilatory determination of, 49–51 threshold (TVENT) development of, 48 measurement techniques, 49–50, 51 Mixed-longitudinal studies, 3 resistance training response, 218–19 Mixed venous carbon dioxide strength and, 62 see also Muscle cross-sectional area concentration (CvCO2) (mCSA) measurement, 143–4 Moderate exercise, 92 sliding filament theory, 49 oxygen uptake kinetics see Oxygen strength see Muscle strength uptake kinetics, moderate exercise striated appearance, 49 Moderate load–high repetition resistance Muscle cross-sectional area (mCSA) training, 222 age-associated development, 51–2, 52 Mood-enhancement by physical isokinetic strength per, 63 activity, 339 measurement, 49–50 Morphological age, peak height velocity measurement site, 50–1 and, 14, 14–15 muscle strength development and, 62–4 Motor unit activation % (%MUA), 65, muscle strength per, 63–4 66, 220–1 sex-associated development, 51–2, 52 Multilevel modelling Muscle fibre(s) advantages, 40–1 age-dependent trends, 84 anaerobic fitness, 110–11, 111 differentiation, 48 definition, 352 fatigue resistance, 93–4 flexibility, 43 metabolic characteristics, 83, 83–4, 84–5 level 1 variation, 41 nature–nurture debate, 112 level 2 variation, 41 sex differences, 85 longitudinal studies, 40, 40–3, 42, 44 type I (slow twitch), 83 muscle strength development and age, 58 age-dependent trend, 84 peak oxygen uptake and, 171, 172, fatigue resistance, 93 172–3, 174 metabolic characteristics, 83 Multiplicative error, 353 oxygen cost of exercise, 93 Muscle(s) shortening velocity, 112 action type IIa (fast twitch - fatigue resistant), definition, 53, 353 83–4 types, 53, 53 metabolic characteristics, 83 venous return effect, 151 shortening velocity, 112 biopsy, 94 type IIX (fast twitch - fatigable), 83–4 anaerobic fitness training response, metabolic characteristics, 83 229, 230 shortening velocity, 112 technique, 84 Muscle–lung transit delay, 192, 200 contraction, 53 Muscle moment see Muscle(s), action fibres see Muscle fibre(s) Muscle moment arm, 353 function, 91, 106 Muscle strength, 47–69 growth/hypertrophy, 48 assessment of, 53–6 length, 51 data interpretation, 55–6 resistance training, 218 habituation period, 55 strength association, 62 isokinetic monoarticular test, 106 innervation, 48 reliability, 55 length, 51 athletes, 311 mass body mass and, 28 anaerobic fitness and, 111–13 definition, 52–3 peak oxygen uptake and, 174 development, 56–66, 57, 58 sex differences, 9, 112, 174 age-related differences, 57, maximal force, 53, 54 57–8, 58 mechanism of action, 49 biomechanical factors, 64–5 pennation, angle of, 65, 112 determinants of, 52, 59–62

Index 371 neuromuscular factors, 65–6 Ontogenetic allometry sex differences, 57, 57, 58, 58–9 definition, 353 isokinetic, 55 limitations, 39–40 isometric, 54, 55 longitudinal studies, 39–40, 40, 43–4 muscle cross-sectional area and, 62–4 resistance training see Resistance training Optimal force (Fopt), 102, 228–9 sex differences, 9 Optimized peak power (PPopt) training see Resistance training Musculoskeletal injuries, resistance age-related changes, 111 training, 217 definition, 353 Myoblasts, 48 force–velocity cycling test, 102, 103 Myofibrils, 49 Optimized pedal velocity (Vopt), 102 Myosin, 48, 49 Osmolality, 353 Myotubes, 48 Osteoblasts, 339 Osteoclasts, 339 N Osteocytes, 339 Osteopenia, 316, 353 NADH/NAD+, 78, 80 Osteoporosis, 316–17 National Children and Youth Fitness definition, 316, 353 physical activity and, 337–9, 338 Study (1985), 56 Overheating in newborns/neonates, 241–2 Nerves/neural factors, 48 Overuse injury, 318–19, 320 Overweight, 334 anaerobic fitness and, 113 see also Obesity growth, 3, 4 Ovulation, hormones, 20 muscle strength development, 65–6 Oxaloacetate, 80, 82 resistance training response, 219–21 Oxidative metabolism, 79–83 Nicotinamide adenine dinucleotide carbohydrate metabolism, 80–1, 81, 82 lipid metabolism, 82–3 (NAD), 78, 80 tricarboxylic acid cycle regulation, 82 Non-contact sports, injuries, 318–20 Oxygen (O2) Non-motorized treadmill (NMT) test arterial partial pressure (PaO2), 124, 132 deficit see Oxygen deficit limitations, 105–6 end-tidal partial pressure (PETO2), 125 maximal intensity exercise, 104–6, 105 uptake see Oxygen uptake (VO2) Wingate anaerobic test versus, 104–5 Oxygen cost of exercise, 193, 203, 206 Non-shivering thermogenesis, 259 Oxygen deficit Noradrenaline, cardiac contractility, 141 definition, 193, 353 Normoxia, 124, 130, 353 heavy exercise, 92 Northern Ireland Young Hearts Project, 336 moderate exercise, 92 Oxygen uptake (VO2), 123 O cardiac output association, 156 kinetics see Oxygen uptake kinetics Obesity, 334, 335 maximal see Maximal oxygen uptake diabetes mellitus and, 335 metabolic syndrome, 336 (VO2max) physical activity and, 326 metabolism estimation from, 236–7 minute ventilation and, 125 Obesity epidemic, 326, 334, 335 peak see Peak oxygen uptake Oesophageal temperature, 240 Oestradiol, 20 (peak VO2) Oestrogen plateauing of, 162–3, 163, 166 response to metabolic demand, 124 growth/matuartion regulation, 20 Oxygen uptake kinetics, 91–3, 189–211 muscle growth inhibition, 61 age-related changes, 199, 199–203, 204, osteoporosis, 316–17 Oligomenorrhoea, 315 204–6, 207 OMNI Scale, 288, 288–90 speed-of response, 208 definition, 353 assessment, 194–7 P-CERT similarities, 289 breath-by-breath basis, 194, 197, 198 validation, 288–90, 292 practical considerations, 194

372 INDEX Oxygen uptake kinetics—(cont’d) linear regression relationship, quantifying the response, 194–7, 33, 33, 34 195, 196 log-linear regression relationship, signal-to-noise ratio, 194, 197 29, 36, 36–7 sex differences, 30, 31 in children, 197–209, 198 definition, 353 exercise intensity domains, 191, 191, determination of, 163, 163–6, 164 equipment, 164 197–9 guidelines, 166 exercise metabolism, 94 limitations in children, 167 heavy exercise, 92–3, 204, 204–7, 205, 207 protocol, 165 factors correlating with, 74 age-related changes, 92–3 growth and, 169–71, 170, 171, 172 models for, 195, 195 heritability, 184 sex differences, 207 longitudinal changes, 39, 40 moderate exercise, 92, 200–4, 201–2 maturation and, 21–2, 168, 172–3, models for, 195, 195, 196 173, 174 principles, 191–7 maximal oxygen uptake versus, 162–3, response model, 191–3, 192, 195, 163, 164 195–6 physical activity and, 339 phase 1 (cardiodynamic phase), 191, habitual, 173–4, 175–6, 177–8 192, 192–3, 197, 199, 199–200, 354 ratio scaling, 28–32 phase 2, 192, 192, 193, 195, 200–3, scaling of, 28–38 201–2, 354 secular trends in, 176, 178–9 phase 3 (steady state), 192, 192, sex differences, 163, 164, 171, 173–5, 174 193, 354 training response, 157, 230–1 primary component gain, 203–4 athletes, 309–10 severe intensity exercise, 208, 208–9 endurance training, 223–4 sex differences, 200, 203, 207 high intensity exercise, 226–7 pre-training level effect, 225, 225–6 P sex differences, 227 Peak post-exercise lactate, 353 Palmitic acid, 83 Peak power (PP) Parasympathetic nervous system, 141–2, age-related changes, 108–9 definition, 353 154 heritability index, 112 Passive paradigm, perceived exertion, longitudinal studies, 110–11 non-motorized treadmill test, 104–5 277–8, 292 recovery from, 113 Peak aortic velocity, 152 sex differences in, 109–10 Peak expiratory flow rate (PEFR), 123 training response, 228 Peak height velocity (PHV), 5, 11–15, 12 Wingate anaerobic test, 32, 32, 101, 102, 108–9, 110 adult height, as percentage of, 14, 14 Peak strength velocity, 60, 64 age at, 5, 11–15 Peak torque, 66 Penis, development of, 16 calculation of, 11–13, 12 Perceived exertion, 275–97 prediction of, 13, 13–14 active paradigm, 277–8 sport-specific, 308, 309 assessment problems, 278 maturity age at, 11 child-specific rating scales, 278–83, 279 morphological age, predictions based see also specific scales on, 14, 14–15 curvilinear scale, 290, 290–1 peak oxygen uptake and, 172 definition, 353 Peak muscle mass velocity, 64 effort estimation and production, 277–8 Peak oxygen uptake (peak VO2) methodological considerations, 292–5 accumulated oxygen deficit test anchoring effort perceptions, 292 see Accumulated oxygen deficit (AOD) test age-related changes, 28, 166–9, 167–8, 170, 170, 171 body mass and, 29, 29–30, 170 allometric relationship, 34–7, 35

Index 373 experimental paradigm Physical fitness, 339–40, 340 comparisons, 292–5, 294 aerobic see Aerobic fitness/power habituation, 292 anaerobic see Anaerobic fitness passive paradigm, 277–8, 292 pictorial ratings of scales, 283–92 Physical inactivity see also specific scales definition, 327 terminology use, 289 prevalence, 327–8 Perceptual continuum, 276, 276–7, 353–4 sex differences in, 327 Performance/situational continuum, 276, tracking of, 341–2 276, 277, 354 unhealthy lifestyle behaviours and, 340 pH, 89, 90, 91, 354 Phenotype, 20 Physiological continuum, 276, 277, 354 Phosphocreatine (PCr) Physique, 305–6, 311–12 anaerobic metabolism response to Pictorial Children’s Effort Rating Table training, 229 exercise metabolism, 75–6 (P-CERT), 286–8, 287 hydrolysis, 76 definition, 354 resynthesis, fatigue resistance and, 94 development, 287 stores, age-dependency, 85 OMNI Scale similarities, 289 Phosphoenolpyruvate (PEP), 78 validity, 287–8 Phosphofructokinase (PFK), 78 Pictorial perceived exertion rating scales, anaerobic metabolism response to training, 229, 230 283–92 exercise metabolism, 85–6 see also specific scales glycolytic pathway regulation, 79 Pituitary gland, 20 3-Phosphoglycerate, 78 Plasma Phosphorylase regulation, 79 composition, 266, 267 Physical activity, 325–46 osmolarity, sweating effects, 244 cardiovascular disease and see triglycerides, 332 Cardiovascular disease Pneumotachograph, 354 childhood, adult health and, 328, 329 Poikilothermal, 354 chronological age-related levels, Population attributable risk (PAR), 22, 23 definition, 343 326, 354 dose–response relationship, 328–9, 330 Power function ratio, 37, 38, 354 future research in, 343–4 growth influence, 20 see also Allometric scaling/modelling guidelines, 326–7, 343, 344 Power output rationale for, 328–31, 329, 330, 331 habitual, endurance training response Children’s Effort Rating Table, 282–3 and, 225–6 training in athletes, 310–11 health and, 331–40, 342–3 Power stroke, 49 intensity, 343 Preload, 141, 150, 152, 354 lifestyles and, 340–1 Premature babies, thermoregulation, 242 maturity-related levels, 20, 22, 23 Prenatal period, 2 measurement of, 342–3 Production-only paradigm, 355 mental health and, 339 Production paradigm, 293–4, 294, 354 osteoporosis and, 337–9, 338 Proximal, definition, 355 patterns in children, 190 Puberty peak oxygen uptake and, 173–4, 175–6, hormone levels, 20 177–8 physical fitness, 339–40, 340 testosterone, 20, 61 sex differences, 176 menarche see Menarche target populations for interventions, sex characteristics, secondary, 16–19, 18 342 Pubic hair tracking of, 341–2 age of attainment, 18 development, 16–17 study alignment, 19 muscle strength development and, 60 peak oxygen uptake and, 172, 173 Pull-ups, 56 Pulmonary function, 119–38 exercise, 123–34 as limiting factor in, 133–4

374 INDEX Pulmonary function—(cont’d) sex differences, 217–18 minute ventilation response to strength increase, 217–18 metabolic demand, 124, 124–9 safety, 216–17 supervision, 216–17 measurement, 123–4 Respiration at rest, 122, 122–3, 123 evaporation loss from, 238 sex differences, 134–5 humoral affecters, 132 structure and mechanics, 120–2 neural affecters, 132 training, adaptation in, 134 venous return effect, 151 ventilation control, 132–3 see also Breathing frequency (fR); ventilation kinetics, 129–32, 130, 131 Ventilation Pyruvate, 78, 80, 87 Respiratory centre, 132 Pyruvate dehydrogenase (PDH), 78, 79 Respiratory compliance, 121 Pyruvate kinase, 86 Respiratory drive, neural, 125 Respiratory exchange ratio (R), 125 R definition, 355 peak oxygen uptake determination, Radiation, 236, 238–9, 242, 259 163, 165 Radiography, 50 substrate utilization estimation, 88 Range of motion (ROM), 54 Respiratory system Rating of perceived exertion (RPE), distensibility (stretchiness), 121 growth changes, 120 276–7 resistance, 121, 128 definition, 349 Roche–Wainer–Thissen method, 15 limitations, 278 Rowing, 309 paradigms for, 277–8 Runners, 304, 307 Ratio scaling (ratio standard) Running speed, age-related, 72, 72, 73 algebraic criterion, 31 body size S cardiac function and, 146–7 Saltation, 5, 355 peak oxygen uptake and, 170 Sarcomere, 49 cross-sectional studies, 28–32, 29–31 Saskatchewan Pediatric Bone Mineral definition, 355 effectiveness assessment, 31 Accrual Study (PBMAS), 17, 18 graphical criterion, 31 Scaling limitations, 30–1, 33–4 muscle strength, 56 definition, 355 Rebreathing techniques, 143–6 objective of, 28 Recall method, menarche age, 15–16 see also specific types Recovery, 113–14 Scrotal skin, development of, 16 exercise metabolism, 93–4, 95 Seasonal influences, relative age effect, 312 maximal intensity exercise, 113–14 Sedentary behaviour, 327–8, 334 Rectal thermometry, 240 Selection into sports, 305, 311–14, 313 Relative age effect (RAE), 312, 313 Self-esteem, physical activity and, 339 Relative age, talent identification, 312 Seminal fluid ejaculation, sexual Repeat-production paradigm, 293, 355 Repetitive microtrauma, 318 development, 17 Repetitive stress, 318 Severe intensity exercise, oxygen uptake, Residual volume (RV), 122, 355 Resistance training, 230 208, 208–9 athletes, 311 Sex characteristics, secondary, 16–19, 18 characteristics, 221–2, 222 components, 216 staging, 16 frequency, 222, 222 training effects, 308 response, 216–22, 230 Sexual maturity muscle size changes, 218–19 determination of, 16 neurological changes, 219–21 sex differences, 17 training effects, 308 Shear stress, blood vessel adaptation, 333

Index 375 Shivering thermogenesis, 259 muscle strength development and, Shortening fraction (SF), 151, 152, 355 59–60, 63–4 Short-term power output peak oxygen uptake, 171 assessment, 73–4 sex differences in, 7 training response, 228–9 sport selection and, 312 Shoulder (biacromial) breadth, 9, 348 sport specific, 301–2 Shuttle runs, peak oxygen uptake Steady-state exercise, 131–2 Stepping protocols, perceived exertion determination, 164 Signal-to-noise ratio, oxygen uptake scales, 285, 287 Strains, 318, 320 kinetics, 194, 197 Strength see Muscle strength Simple linear equation, 355 Stress fractures, 318–19 Sinoatrial node (SA node), 141–2, 149 Stress reduction by physical activity, 339 Sitting height, 5 Stroke index (SI), 146, 147 Skeletal age, 10–11 age and, 148, 153 assessment, 10–11, 15 definition, 355 chronological age versus, 11 sex differences, 148, 153, 175 Skills performance, mesomorphy Stroke volume (SV), 140, 140–2 age-related changes, 148, 152–3 association, 305–6 body position effects, 147–8, 150, 150 Skinfold thickness body size and, 146 cardiac output association, 156 body fat in athletes, 305 definition, 140–1, 355 heat loss and, 261 exercise, response to, 150, 150–4, 151 muscle size measurement, 49 maximal, 153, 175 Skin temperature, 240 measurement, 142–6 Sliding filament theory, 49 Slow component, 355 invasive methods, 142–3 Slow twitch muscle fibre see Muscle fibre, non-invasive methods, 143–6 see also specific methods type I (slow twitch) plateauing of, 152 Smoking, 344 at rest, 147–8 Soccer sex differences, 148, 153–4, 175 trainability of, 157 body mass, 304 Study design, 3 peak height velocity, 309 secondary sex characteristics, sports injury in, 319, 320 alignment by, 17–18 stature, 302, 302 see also Cross-sectional studies; Sodium ions, fluid intake with, 268, 268–9 Longitudinal studies Somatic maturity, 17 Subischial length, 5 Somatotyping, 305–6, 355 Submaximal exercise Specific latent heat of vaporization, 355 blood lactate, 87 Sports injuries, 317–21, 319 lactate threshold, 181 contact sports, 320–1 stroke volume, 152, 153 non-contact sports, 318–20 substrate utilization, 79–80 risk factors, 318, 319 Substrate utilization, 79–80, 88, 94 Sports, selection into, 305, 311–14, 313 Succinate dehydrogenase (SDH), 85–6, 229 Sprains, 318, 320 Succinyl CoA, 80 Static muscle actions, 355 Supramaximal electrically evoked muscle Statis, 5, 355 stimulation, 65 Stature Sweat adult, 7 composition, 266, 267 evaporation, 237–8 measured height as a percentage of, latent heat of vaporization, 237 14–15 Sweating/sweat response peak height velocity and, 14, 14 age-related differences, 247–50 age-related changes, 5, 6 effects of, 244 athletes, 301–3, 302, 303, 312 definition, 5 diurnal variation, 5 growth, 5–7, 6, 28 isometric torque and, 64

376 INDEX Sweating/sweat response—(cont’d) Thermal balance see Heat balance exercise in the heat, 254–5, 256 Thermal conductivity coefficient, 237 fluid loss levels, 266, 267 Thermal strain, 356 heat acclimation and, 265 Thermal stress, 356 initiation in acclimatization/ Thermodilution method, 143 acclimation, 261–2 Thermogenesis, 259, 261 initiation of, 243 Thermoneutral zone (TNZ), 241, 356 maturation differences, 243 Thermoregulation rate of, 238 sex differences, 243 age-related differences, 258 volume of fluid loss, 244 cold environment, 250–1, 252 exercise in dry heat, 255 Swimmers hot environment, 250–1, 252 body composition, 304 hypothalamus, 240, 241, 242 body mass, 304 outside the neutral zone, 241–2 maturity status, 307 see also Heat balance menarche, age at, 306 Thigh muscle, measurement of, 49–50, 51 pulmonary adaptation to training, 134 Thirst, 268, 269 sports injury in, 320 Thoracic electrical bioimpedance (TEB), stature, 301–2, 302, 303 thermoregulation, 259, 261 145–6 Thorax, 120, 122 Sympathetic nervous system Tidal volume (VT), 122, 127–9, 128 cardiac drift, 155, 155 cardiovascular function, 141–2 breathing frequency ratio, 127–9 heart rate regulation, 154 definition, 356 venous return influence, 151 response to metabolic demand, 124 Time constant (τ), 356 Syndrome X, 336, 356 Time to peak torque (TPT) electrical Systemic vascular resistance, 141 stimulation, 220–1 T Torque, 64–5, 220–1, 356 Total lung capacity (TLC), 120, 122, 122 Talent selection and development, 311–14 definition, 356 sex differences, 134 ‘Tanner stages’, 16 Total mechanical work (TMW), 113 Tanner–Whitehouse ‘bone specific scoring’ Tracking, 341–2, 356 Training technique, 10–11 body fat effects, 305 Temperature see Body temperature; cardiovascular function, 157–8 definition, 301 Environmental factors/temperature factors of, 301 Tennis players goals, 214 growth effects, 302–3 body mass, 304 maturation effects, 306 bone mineral density, asymmetrical, 304 menarche effects, 307 stature, 301–2, 302, 303 oxygen uptake kinetic adaptation, 207 Testes enlargement, 16 principles, 215–16 Testosterone pulmonary adaptation, 134 anaerobic fitness and, 113 response, 213–34 blood haemoglobin concentration and, aerobic fitness see Aerobic training, 174–5 response definition, 356 anaerobic performance see growth/maturation regulation, 20 Anaerobic fitness, training response muscle size, 218, 219 muscle strength see Resistance muscle strength development and, 61 training, response puberty and, 20, 61 physiological parameters, 214–15 Tetanic electrically evoked muscle research designs, 215–16 see also specific types stimulation, 65–6 Traumatic injuries, 320 Tethered sprint test, 104 ‘The deadly quartet’, 336, 356

Index 377 Treadle ergometer, calf muscle exercise, Ventricular end-systolic diameter (ESD), 90–1 150, 151, 151–2 Treadmills Very low-density lipoproteins (VLDL), oxygen uptake assessment, 194 332, 357 peak oxygen uptake determination, 164, 165 Vital capacity (VC), 122, 357 age-related effects, 167, 167 Volleyball longitudinal studies, 167–9, 168 see also Non-motorized treadmill body size, 311–12 (NMT) test menarche, age at, 306 stature, 301–2 Tricarboxylic acid cycle (TCA), 80, 81, 82, Voluntary dehydration, 269 356 Voluntary exhaustion, 165 ‘Trigger hypothesis’, 223 W Triglycerides, 82, 332 Tropomyosin, 49 Waist to hip ratio (WHR), 334 Troponin, 49 Warm environment, 357 Turbine flow meter, 356 Warm receptors, 241 Twitch torque (TT) electrical stimulation, Water 220–1 hydration, 268, 268 Two-part biocultural hypothesis (genetic see also Fluid intake predisposition theory), 307 intoxication, 244 Tympanic membrane temperature, 240 submergence, 259 see also Fluid balance U Weight-bearing sports, 304 Weight preoccupation, 314–15 Ultrasonography, 50 Wet bulb globe thermometer (WBGT), V 239–40 Wind-chill, 238, 357 Vasoconstriction, 241, 259 Wingate anaerobic test (WAnT), 101–2 Vasodilation, 242–3 ATP resynthesis, 76 cold, physiological response to, 259 indicators in, 101 thermoneutral zone maintenance, 241 limitations, 101–2 Velocity, 356 longitudinal studies using, 110 Venous return mean power, 101, 102, 108–9, 110 definition, 356 non-motorized treadmill test versus, factors that increase, 150–1 heart rate and, 152 104–5 stroke volume and, 141 peak power, 32, 32, 108–9, 110 Ventilation post-exercise blood lactate body temperature elevation concentration, 106–7, 110 effects, 244 recovery from maximal intensity control, 132–3 kinetics, 129–32, 130, 131 exercise, 113, 114 minute see Minute ventilation (VE) reliability, 101 Ventilatory drift, 131–2 short-term power output assessment, Ventilatory threshold (TVENT), 124, 125–7 definition, 356 73–4 estimation problems, 127 training response studies, 228 exercise intensity domain distinction, validity, 101 Work, heat balance, 236, 239 191, 197–8 Wrestling, 319 rating of perceived exertion and, 278 Ventricle, left see Left ventricle Y Ventricular end-diastolic diameter (EDD), ‘Young and Active’, 327 146, 150–1, 151 Young athlete, 299–324 aerobic performance, 309–10 anaerobic performance, 310–11

378 INDEX Young athlete—(cont’d) physique, 305–6, 311–12 body composition, 304–5 selection into sports, 311–14, 313 body mass, 304–5 sports injuries see Sports injuries body size, sport selection, 311–12 stature, 301–3, 302, 303, 312 definition, 300 training, 301 female athlete triad see Female athlete triad Z growth, 301–9 maturation, 306, 306–8, 309, 312, 313 Z lines, 49 muscle strength, 311 physical performance, 309–11