Dissociation between skinfold thickness changes and growth of adipose tissue volume in children and youth

The purpose of this investigation was to determine whether there is a divergence in the relationship between skinfold thickness and an adipose tissue volume (ATV) corresponding to the same segment of the body during growth. Anthropometric data from the cross-sectional Coquitlam Growth Study (COGRO) were used to estimate the ATV of the arm, calf, thigh, and trunk in 6- to 18 years old girls (n = 458) and boys (n = 487). Assuring a cylindrical shape for body segments, ATV was calculated by subtracting an inner cylinder of muscle, bone, and residual from the total cylindrical volume of a given segment. Combined graphical analysis of both skinfold growth and growth of ATV reveals that a decrease in skinfold can occur without a concomitant decrease in its corresponding regional ATV. This happens more dramatically in boys than in girls, and in the limbs than in the trunk. This suggests that exaggerated growth in length and/or muscle girth cause a "spreading" and "thinning" of the adipose tissue layer, which does not necessarily reflect fat loss. The meaning of changes in skinfold thicknesses during growth thus needs evaluation. © 1995 Wiley-Liss, Inc.