Abstract

Introduction: Obesity in adolescents increases the risk of chronic diseases. Studies have shown that increasing physical activity improves metabolic health. However, there is a divergence regar-ding the effectiveness of different types of physical activity programs in adolescents.Objective: To determine the effects of two physical activity programs on early adolescents with obesity, and to compare their benefits on body composition and metabolic markers.Methodology: 35 adolescents diagnosed with obesity from a public school were selected and ran-domized in two groups. The HIIT group (n = 18) performed 1 min of intense exercise at 80-100 % of the maximum heart rate (HRmax) and rested 2 for a min, repeating this cycle 10 times; the MICTgroup (n = 17) performed 30 min of continuous exercise at 55-69% of HRmax. Both exercise pro-grams were performed on a static bike, 3 times per week, for 12 weeks. All the participants had nutritional counseling weekly.Results: We detected a statistically significant increase in the lean mass (p = 0.008 and p = 0.002) and a decrease in triglyceride levels (p = 0.080 and p <0.001), for the MICT and the HIIT groups, respectively. Conclusion: Both exercise programs in conjunction with nutritional counseling, lead to a signifi-cant increase in lean mass and a decrease in triglyceride levels. MICT had a greater impact in decrea-sing fat mass, and both had a similar impact in reducing triglycerides levels. Keywords: Obesity, adolescent health, exercise and physical activity, school health, health promotion.