ACSM's Health-Related Physical Fitness Assessment Manual SECOND EDITION

60 ACSM's HEALTH-RELATED PHYSICAL FITNESS ASSESSMENT MANUAL· www.acsm.org BD = 83,620 78,310 =BD 1.0678 = _% Body Fat ~ 450 1.0678 % Body Fat = 13.6% SUMMARY OF BODY COMPOSITION METHODOLOGY HeightlWeight Tables: • Subjective • May be based on a limited sample of clients who sought out life insurance • Problem with the definition of frame size (visual or elbow breadth) • Problem with the definition of overweight versus overfat Body Mass Index (BMI): • Simple calculation of the ratio of height to weight (similar concerns as height/weight tables) • Popular with large scale (epidemiological) studies • Good morbidity and mortality statistics available Waist-to-Hip Ratio (WHR): • Simple measure to obtain • Ratio is not interpretable by itself • The association of WHR to morbidity and mortality is impressive and perhaps causal • Can use waist circumference alone Circumferences (girths): • Many formulas for converting to percent body fat • Problem of girth size not directly related to fat • Fairly simple yet not as accurate as skinfolds • May be a good method for demonstrating body composition, or size, changes over time Skinfolds: • Highly regarded technique, yet prone to error • Technician training important • Anatomical site selection crucial • Many skinfold formulas exist from one site up to 10 sites and some formulas that combine with some circumference measures • Not more accurate than underwater weighing, privacy issue Bioelectrical Impedance Analysis (BIA): • Newer technique that attempts to eliminate technician error • Dependent on many assumptions that client must meet (e.g., body water or hydration level) • No more accurate than skinfolds and more costly; probably quicker than skinfolds and less privacy required Underwater Weighing (hydrostatic or densitometry): • Time consuming • Costly in equipment and technicians, training