Effects of Resistance Training on Obese Adolescents

Purpose The effects of resistance training (RT) alone upon endothelial function, metabolic and hemodynamic profiles, physical fitness, body composition, and inflammatory biomarkers in nondiabetic obese adolescents were investigated. Methods Adolescents were assigned into nonobese control (CG, n = 20; 14.7 1.4 yr) and obese (OB, n = 24; 14.1 1.0 yr) groups. Muscle and skin endothelial reactivity, body composition, at-office and 24-h ambulatory blood pressure, metabolic profile, adipocytokines, aerobic and strength fitness were assessed before and after 12 wk of RT (CG, only at admission). Results After RT, body mass did not change in OB, but significant reductions in body fat (1.6%; P = 0.01), waist circumference (2.9%; P < 0.001), waist-to-hip ratio (3.3%; P < 0.001), homeostasis model assessment for insulin resistance (15.4%; P = 0.02), endothelin-1 (14.2%; P = 0.04), and fibrinogen (6.9%; P = 0.03) were found. Both at-office and ambulatory blood pressure decreased, whereas skin endothelium-dependent vasodilation (32%; P = 0.02), VO2 (14.3%; P = 0.04), and HR (5.3%; P = 0.04) during submaximal exercise and isokinetic strength (extension, 21.3%; flexion, 29.9%; P < 0.0001) increased. Forearm vascular conductance increased at rest (28.1%; P = 0.03) and during postocclusive reactive hyperemia (25.2%; P = 0.02). After RT differences between CG and OB at admission were no longer detected for most outcomes. Conclusions RT alone improved endothelial function, hemodynamic and metabolic profiles, body composition, and physical fitness in nondiabetic obese adolescents regardless of changes in body mass.