Role of exercise in the prevention of obesity and hemodynamic abnormalities in adolescents.

BACKGROUND: Poor physical activity plays a key role in the development of obesity. Little is known, however, about how much or the level of intensity of exercise that is needed to prevent obesity and hemodynamic abnormalities in adolescents. METHODS AND RESULTS: Height, bodyweight, resting heart rate (HR), and systolic and diastolic blood pressure was measured in 17,523 male and 16,906 female high school students. Self-reported exercise intensity was related to percentage of overweight (POW), diastolic blood pressure, and resting HR in boys, and to bodyweight and resting HR in girls. Self-reported exercise amount was associated with POW, diastolic blood pressure, and resting HR in both boys and girls. Also, high intensity or adequate amount of exercise was associated with a lower prevalence of obesity and resting tachycardia in both sexes, and slightly associated with the prevalence of systolic high blood pressure in boys. CONCLUSION: Both intensity and amount of exercise are associated with the prevalence of obesity and hemodynamic abnormalities in adolescents.