Efficacy of aerobic exercise program on anthropometric measurements and glucose metabolism in obese adolescents with impaired glucose tolerance : A randomized

Introduction: Although physical activity improves the body composition and minimizes risks of metabolic diseases, whether different exercise programs result in similar effects on anthropometric measurements and pancreatic β-cell function is not clear. The purpose of this study was to verify whether a home-based walking program has the same effects in anthropometric measurements and pancreatic β-cell function as a center-based aerobic exercise program. Methods: Obese adolescents with impaired glucose tolerance (n=33) were recruited and randomly assigned to a center-based program (CP) group (exercise on a treadmill with moderate intensity for 30 min, 3 times per week for 8 weeks; n=11), a home-based program (HP) group (walk with a pedometer to accumulate 10,000 steps per day for at least 3 days per week for 8 weeks; n=11), or a control (CG) group (maintain ones normal daily activities; n=11). Anthropometric parameters and pancreatic β-cell function were measured at the baseline and after 8 weeks of exercise programs. An analysis of covariance (ANCOVA) was conducted to test the overall effects. Results: Both exercise groups showed significant improvements in the fat mass (-1.58 vs. -1.80)(F=9.95, p < .001), waist circumference (-3.78 vs. -4.88)(F=12.24, p < .001), hip circumference (-1.55 vs. -2.25) (F=17.90, p < .001), and waist-hip ratio (-0.02 vs. -0.03)(F=4.28, p = .025) compared to the control group. Pancreatic β-cell function in both exercise groups significantly improved, which was reflected by the insulin action by insulin sensitivity (BIGTT-SI)(0.60 vs.0.63) (F=6.89, p = .004) and deposition index (DI) (5.54 vs. 5.66) (F=7.51, p < .001). Differences in all measurements between two groups were not observed. Conclusion : The findings suggested that a home-based walking program has similar effects as center-based aerobic exercise program on anthropometric measurements and pancreatic β-cell function.