T. Hortobagyi et al., COMPARISON OF BODY-COMPOSITION ASSESSMENT BY HYDRODENSITOMETRY, SKINFOLDS, AND MULTIPLE SITE NEAR-INFRARED SPECTROPHOTOMETRY, European journal of clinical nutrition, 46(3), 1992, pp. 205-211
Percent body fat (%BF) was assessed in 171 men with underwater weighin
g (UWW), seven-site skinfolds (7 SF), and near-infrared spectrophotome
try (NIR). NIR was determined at eight sites, including biceps, tricep
s, axilla, chest, abdomen, suprailium, subscapula and thigh. Analysis
of variance and Dunnett's post-hoc procedure revealed that NIR signifi
cantly (P < 0.05) underpredicted %BF when using the biceps (12.9%), ch
est (11.3%), abdomen (10.2%), subscapula (11.3%) and thigh (9.9%) site
s compared to the criterion %BF measured with UWW (13.4% +/- SD = 6.49
). %BF with 7 SF was only 0.3% higher than %BF with UWW (r = 0.94), st
andard error of estimate = 2.9%). Correlation coefficients between SF
thickness and NIR optical density readings at 940nm (OD1) and 950nm (O
D2) wavelengths ranged from r = -0.30 (subscapula) to r = -0.67 (bicep
s) for OD1 and r = -0.39 (axilla) to r = -0.68 (biceps) for OD2. Multi
ple linear regression showed that the OD readings were not significant
predictors of UWW %BF when using body mass, stature, activity level,
and frame size as predictors, except for the OD2 reading at the biceps
site. Stepwise regression revealed that NIR OD readings did not predi
ct additional variance in %BF beyond mass, stature, activity level, fr
ame size, or 7 SF. It was concluded that 7 SF are better predictors of
%BF than NIR, and that NIR at multiple sites is inconsistent in asses
sing body composition.