Effect of race and musculoskeletal development on the accuracy of air plethysmography.
OBJECTIVE
The purpose of this study was to determine the effect of race and musculoskeletal development on the accuracy of estimates of body fatness (%fat) via air displacement plethysmography (AP).


METHODS
Estimates of %fat were made via AP, hydrostatic weighing (HW), dual-energy x-ray absorptiometry (DXA), and the criterion, a four-component model (4C) in 64 black (B) and white (W) men, who were either resistance trained (RT) or served as controls (C).


RESULTS
Based on a three-way ANOVA, there were no statistically significant three-way or race x musculoskeletal development interactions. There was no main effect of race on the validity of estimating %fat by AP; the mean bias between %FatAP and %Fat4C was similar for B (3.6% body fat) and W (3.7%). In addition, the density of the fat-free mass (Dffm) for B (1.098 +/- 0.002 g x mL) was not different than 1.10 g x mL. There was a significant effect of musculoskeletal development on the validity of the estimation of %fat from AP; the mean difference in %fat between %FatAP and %Fat4C was less in RT (1.5% body fat) than in C (5.3%), but a large SEE of 5.5% was observed for RT. A significant (P < 0.05) correlation was found between the mean bias between methods and body volume (-0.44) and mesomorphy (-0.55).


CONCLUSIONS
Race does not affect the accuracy of estimating %fat by AP. Race-specific equations estimating %fat via densitometry (e.g., AP, HW) such as the Schutte are not justified, because Dffm is not greater than 1.10 g x mL. Estimation of %fat via AP is more accurate in larger individuals with high musculoskeletal development as a group, but individual results are highly variable.
Collins
Mitchell A
MA
Exercise Physiology Laboratory, School of Applied Physiology, Georgia Institute of Technology, Atlanta, GA, USA. mcollins@kennesaw.edu
Millard-Stafford
Mindy L
ML
Evans
Ellen M
EM
Snow
Teresa K
TK
Cureton
Kirk J
KJ
Rosskopf
Linda B
LB
D015502:Absorptiometry, Photon; D000886:Anthropometry; D044383:Black People; D001834:Body Water; D006801:Humans; D009142:Musculoskeletal Physiological Phenomena; D010991:Plethysmography / Q000379:methods / Q000592:standards*; D014481:United States; D044465:White People; D001741:Black or African American