Maximal aerobic power in 13- and 14-year-old teenagers in relation to biologic age.

Maximal oxygen uptake (VO2 max) was measured on a treadmill in 375 teenagers, 13 and 14 years old. VO2 max per kg body mass in boys had a mean value of 59 ml. min-1.kg-1 and in girls of 51 ml.min-1.kg-1. Linear regression analysis across biologic age revealed that in boys as well as in girls the VO2 max increased with increasing biologic age. However, per kg body weight or per kg lean body mass VO2 max decreased. VO2 max per cm height squared and per kg body mass to the two-thirds power did not show a change with biologic age. Multiple regression analysis revealed that the increase in the absolute values of the VO2 max and the decrease in the relative values of the VO2 max with increasing biologic age was almost completely due to the increase in total body mass (i.c. height and weight).