Evaluation of the BOD POD for Estimating Percent Fat in Female College Athletes

Abstract

The purpose of this investigation was to examine the accuracy of percent body fat (%BF) estimates obtained by air displacement plethysmography (ADP) using the BOD POD Body Composition System compared with hydrostatic weighing (HW) in a group of female college athletes (n = 80). In addition, %BF estimates by skinfold measures (SF) were also obtained for comparison. A lean subset (n = 39) of the sample was also examined. Mean %BF estimated for the entire sample by ADP (21.2 +/- 5.9%) was significantly greater than that determined by HW (19.4 +/- 6.4%) and SF (18.8 +/- 5.5%). Results from the lean subset also revealed that %BF determined by ADP (17.1 +/- 3.7%) was significantly higher than %BF estimates by HW (14.3 +/- 2.8%) and SF (15.2 +/- 3.2%). The regression equation for the entire sample (%BF HW = 0.937%BF ADP - 0.452, r(2) = 0.73, standard error of estimates (SEE) = 3.34) did not differ from the line of identity. In contrast, the line of identity differed significantly from the regression equation for the lean subset of female athletes (%BF HW = 0.48%BF ADP + 6.115, r(2) = 0.41, SEE = 2.18). The results of this investigation indicate that ADP significantly overestimated %BF by 8% in female athletes and by 16% for a leaner subset of the sample compared with HW. It appears that %BF estimates by SF may be more accurate than those obtained by ADP for female college athletes, regardless of body composition. Coaches and trainers evaluating body composition should consider the use of SF before ADP when measuring %BF in female college athletes. Sports scientists should continue to examine the possible gender and body composition bias for ADP.

Validity and Reliability of the BOD POD®S/T Tracking System

“…The BOD POD ® S / T, however, provided reliable % BF values within-and between-days amongst the sample male and female subjects. Generally, fi ndings from the current study both contrast [3,4] and concur [14,20,21] with the literature examining the validity and reliability values between the BOD POD ® and other forms of body composition assessment tools (e. g., hydrodensitometry and skinfolds). While the authors of this paper could specifi cally reiterate the vast comparative BOD POD ® literature [2,5,6,11,16,22] , this would, however, not serve to support the impetus of the investigation, which was to determine the validity and reliability of the BOD POD ® S / T assessment tool, not its parentcounterpart, the BOD POD ® .…”

A comparison of body composition measurement techniques

“…However, the results of the present study highlight the differences between ADP and BIA compared to different skinfold equations, with the least variation reported between ADP and the Jackson & Pollock (1978) and Jackson et al (1980) skinfold equations compared to BIA and the Durnin & Womersley (1974) skinfold equation. Previous evidence has reported accurate % BF estimations when using skinfold equations compared to ADP and HW (Vescovi et al, 2002). However, in contrast, Kilduff et al (2007) indicated that between-day differences using the Jackson & Pollock (1978) equation where not within the acceptable limits compared to ADP, BIA and HW.…”

Body composition for health and performance: a survey of body composition assessment practice carried out by the Ad Hoc Research Working Group on Body Composition, Health and Performance under the auspices of the IOC Medical Commission

“…For this two-component method, body density depends on the given athlete having both normal BMD as well as a normal hydration status at the time of measurement. Variation in both areas can influence the fat free component and this is well documented in athletes,13 14 thus limiting the use of ADP and other densitometry techniques such as underwater weighing for the athletic population 2…”