Journal of Applied Physiology, Vol 40, Issue 3 300-304, Copyright © 1976 by American Physiological Society
Prediction of body density in young and middle-aged men
M. L. Pollock, T. Hickman, Z. Kendrick, A. Jackson, A. C. Linnerud and G. Dawson
The purpose of this investigation was to predict body density of young
(18-22 yr) and middle-aged (40-55 yr) men and to determine if generalized
equations were appropriate to both populations. The dependent variable,
body density, was determined by the hydrostatic technique. Independent
variables included 7 skinfold fat, 11 girth, and 7 diameter measures; age;
height; and weight. Mean body density for young men was 1.068 g/ml (SD +/-
0.014) and percent fat, 13.4 (SD +/- 6.0); the values for middle-aged
subjects were 1.043 g/ml (SD +/- 0.0130) and 24.7% (SD +/- 5.9). Incomplete
principal components analysis was used to examine the dimensions measured
by the independent variables, and these analyses revealed differences
between samples. Using multiple regression analysis, with the exception of
girth measurements, the slopes of the regression lines were equal. For all
analyses, however, the intercepts were different. These results confirmed
the need for different regression equations for these populations. The most
accurate prediction for young men was with two skinfold, four girth, and
two diameter measures (R = 0.88; SE = 0.0069 g/ml); two skinfold and three
girth measures accurately predicted body density for middle-aged men (R =
0.84; SE = 0.0074 g/ml).
