Body composition in athletes: A comparison of densitometric methods and tracking of individual differences

Abstract Measuring body composition in athletes can provide valuable information on training and nutritional status. The aim of this study was to compare percentage body fat (PF) obtained by hydrostatic weighing (HW) to PF via air-displacement plethysmography (ADP), and to evaluate tracking of individual differences between both methods over time in elite college athletes. Thirty-one male and 33 female athletes (18.0–36.4 years) were measured by ADP and HW. Twenty-one subjects (10 men, 11 women) were measured again 61±11 days later to evaluate consistency of individual differences between methods. Mean PF differed significantly in men (HW: 9.4±2.4%, ADP: 11.3±3.4%, P<0.05) but not in women (HW: 19.1±2.4%, ADP: 19.5±3.7%). A significant trend in mean bias was found in both genders between HW-ADP suggesting an underestimation of PF by ADP at lower mean PF and an overestimation of PF by ADP at higher mean PF. Up to 73% of variance in differences between methods at follow-up was explained by differences betwe...