Differences and changes in VO2 among young runners 10 to 18 years of age.

Twenty young males, all active in middle-distance running, were studied between January 1968 and May 1974 for the purpose of gathering longitudinal data regarding Vo2 during treadmil running. Vo2 submax (measured during the last 2 min of a 6-min run at 202 m/min) and Vo2 max values (measured during a 5-8 min increasing-speed run to exhaustion) were collected approximately every 6 months for 6 years. Different groups, starting at ages of 10, 12 and 13 years were followed for periods of 2 to 5 years continuously. In all longitudinal comparisons. Vo2 max (ml/min) changes peralleled changes in body weight; consequently, Vo2 max (ml/kg.min-1) did not show a significant change. In every group Vo2 submax (ml/kg.min-1) dropped significantly over time. All data were pooled by 1 yr age groups, providing cross-sectional data for active boys 10-18 yrs of age. Vo2 max ranged from 1933 ml/min for 10-yr olds to 4082 for 18-year olds. Concurrent changes in weight resulted in no significant differences in Vo2 max (ml/kg.min-1) from the overall mean of 61.5 Vo2 submax (ml/kg.min-1) was highest among 10-year olds (53.3) and lowest among 18-yr olds (42.5). Based on these longitudinal and cross sectional findings and significant improvements in times for 1- and 2-mile races, it was concluded that Vo2 max (ml/min) increases no faster than does body weight among moderately active growing boys and that both age and training contribute to a change in Vo2 submax; a factor which accounts greatly for improvements in middle-distance race performance.