Influence of maturation on relationship of skinfolds to body density: A cross-sectional study

The purpose of this study is to assess the influence of maturation of skinfold thickness to body density A 4 x 2 x 2 factorial plan was used with children (N = 232) and adults (N = 85) representing four maturation groups of males and females and Black and White subjects. The subjects were measured at nine skinfold sites, and body density by underwater weighing with functional residual lung volume. From the nine skinfolds, four sites (triceps, calf, thigh, and abdomen) were found to be the best predictors of body density in both samples of children. The mean body density (gm/cc) corresponding to the mean sum of four skinfold values of 50 mm for males was 1.046 gm/cc for the prepubescent, 1.050 gm/cc pubescent, 1.057 gm/cc postpubescent and 1.055 gm/cc for adults. For females, the mean densities were 1.038 gm/cc prepubescent, 1.043 gg/cm pubescent, 1.048 gm/cc postpubescent, and 1.046 gm/cc adults. Significant changes (p < .05) in the relation of the sum of four skinfolds to density occur from prepubescence to pubescence and from pubescence to postpubescence. These results have important implications for estimating body fatness in children from anthropometric-density relationships, since adult anthropometric equations overestimated the body density of children and thus underestimate body fatness. Therefore equations developed on children to estimate body density are needed. Additionally, these data suggest that the density of the fat-free body changes with maturity, indicating that the relationship of density to body fatness in children needs further investigation.