Skeletal age and submaximal working capacity in boys.

Skeletal age (SA) and Vo2 at a heart rate of 130 (Vo130) during work on a bicycle ergometer were measured in 237 boys 8-18 years of age. Analysis indicates that Vo130 is well correlated with SA, but also is equally well correlated with chronological age (CA), height and body weight. Age-specific correlations show that Vo130 is associated with SA from 12 through 16 years of age. Partialing out SA results in a significant decrease in the correlations of either height or weight with Vo130 only in the 12-16 year subgroup. The total common variance explained in Vo130 when regressed over CA, height and weight is affected by the presence of SA only in the 12-16 age subset. In spite of the high degree of multicollinearity among the independent variates, correlation data seem to indicate that SA and Vo130 have a slightly higher degree of relationship circumpuberally, i.e. between 12 and 16 years of age.