Influences of exercise interventions on overweight and obesity in children and adolescents

Purpose Conflicting findings of the effects of exercise on body fat, free fat mass, insulin, insulin resistance, and physical fitness for overweight and obesity in children and adolescents. The purpose of this meta-analysis was to investigate the effects of exercise interventions in children and adolescents with overweight and obesity depending on exercise type and to build effective exercise interventions to reduce risks of metabolic disorders. Methods Databases were used to find eligible studies regarding the effects of exercise interventions on overweight and obesity in children and adolescents in randomized controlled trails. Effect size was calculated using the standardized mean difference statistic and heterogeneity across studies was estimated using the Q statistic. Results A total of 27 studies met the inclusion criteria. Children and adolescents with overweight and obesity who participated in aerobic exercise had reduced body mass index, % body fat, fasting insulin, free fat mass, TNF-alpha, and IL-6, and increased physical fitness compared with control groups. Reduced free fat mass in resistance exercise was not found. Glucose, insulin resistance, blood pressure, C-reactive protein (CRP), and blood markers including total cholesterol (TC), triglyceride, LDL, and HDL did not have significant change. Average exercise interventions were aerobic exercise, 3 times/week, 60 min, and 36 weeks of exercise period. Conclusions Aerobic exercise may be beneficial to reduce body fat, fasting insulin, and inflammatory markers, and increased physical fitness for overweight and obesity in childhood and adolescence, but resistance exercise may be added, which can help avoid muscle loss in children and adolescents with overweight and obesity.