The purpose of this study was to examine the stability of somatotypes
of 63 boys in Saskatoon, Canada who were followed from 7 to 16 years o
f age. Somatotype photos were taken annually and rated by a criterion
rater (BH-R). Comparisons were made longitudinally across all years us
ing repeated-measures ANOVAs of the whole somatotype (S), somatotype a
ttitudinal means (SAM), analysis of categories, separate components (e
ndomorphy, mesomorphy, ectomorphy), and partial correlations. In the f
irst year the means were age = 7.1 yr, height = 121.0 cm, mass = 22.8
kg, S = 2.9-3.6-1.6, and SAM = 1.1. In the last year, the means were a
ge = 16.7 yr, height = 172.6 cm, mass = 59.9 kg, S = 2.5-4.0-3.7, and
SAM = 1.4. Mean somatotypes across years were different [F-(9,F-558) =
67.9, P < .01], with the largest differences between 7-10 yr and 14-1
6 yr. These differences were largely due to significant increases in m
esomorphy (F = 24.6, P < .01) and ectomorphy (F = 159.9, P < .01). Par
tial correlations between ages for each component, with the other two
held constant, revealed poor predictions for three or more years apart
(r(2) < .35). Thus, both group and individual somatotypes changed bet
ween 7 and 16 years of age. The overall pattern was from endo-mesomorp
h through central to mesomorph-ectomorph somatotypes. The trends are s
imilar to those observed in comparable samples from other countries. (
C) 1997 Wiley-Liss, Inc.