Insulin and weight status in adolescents: independent effects of intensity of physical activity and peak aerobic power.

Differences in insulin concentrations between normal weight or overweight adolescents (n = 437) were determined depending on their habitual physical activity (PA) and aerobic power (pVO2max). Tertiles were computed for PA (survey) and pVO2max (submaximal predicted cycle test). Independent of their weight, adolescents in the upper 2 tertiles for vigorous PA had lower insulin concentrations than those in the bottom tertile (p < .05). Adolescents in the top tertile for pVO2max expressed per kg fat-free mass also had lower insulin concentrations than those in the medium and bottom tertiles (p = .002). In youth, vigorous physical activity and aerobic power are associated with fasting insulin independent of weight status.