Statural growth (size attained), age at peak height velocity (PHV), and growth rate were compared in two samples of boys classified as habitually physically active and inactive, and in two samples of boys regularly training in sport (primarily team sports). Individual growth records were fitted mathematically in three of the samples (two as reported by the respective authors and one for the present report), while curves were fit to group means for the fourth sample. There were no differences in size, age at PHV, and PHV between active and inactive boys, but the parameters of the adolescent spurt for boys regularly involved in sport were characteristic of early maturers. Longitudinal data are less extensive for girls. Stature data for three samples of young athletes in gymnastics, swimming, and track/rowing indicated a stable pattern relative to reference data for nonathletes, i.e., swimmers, track athletes, and rowers were already taller and gymnasts already shorter than average during childhood and maintained their position relative to reference data during childhood and adolescence. Allowing for sample size and variation in descriptions of habitual physical activity and training for sport, the data suggest that regular physical activity, sport participation, and training for sport have no effect on attained stature, timing of PHV, and rate of growth in stature. Prospective data for the swimmers, track athletes, and rowers indicate no effect of training on the timing of menarche.