The effects of a combined strength and aerobic exercise program on glucose control and insulin action in women with type 2 diabetes

The purpose of the present study was to investigate the short- and long-term effects of a combined strength and aerobic training program on glycemic control, insulin action, exercise capacity and muscular strength in postmenopausal women with type 2 diabetes. Nine postmenopausal women, aged 55.2 (6.7) years, with type 2 diabetes participated in a supervised training program for 4 months consisting of two strength training sessions (3 sets of 12 repetitions at 60% one-repetition maximum strength) and two aerobic training sessions (60-70% of maximum heart rate at the beginning, and 70-80% of maximum heart rate after 2 months). Anthropometrical measurements, percentage glycated hemoglobin, a 2-h oral glucose tolerance test, exercise stress testing and maximum strength were measured at the beginning, and after 4 and 16 weeks of the exercise program. Significant reductions were observed in both the glucose (8.1% P<0.01) and insulin areas under the curve (20.7%, P<0.05) after 4 weeks of training. These adaptations were further improved after 16 weeks (glucose 12.5%, insulin 38%, P<0.001). Glycated hemoglobin was significantly decreased after 4 weeks [7.7 (1.7) vs 7.1 (1.3)%, P<0.05] and after 16 weeks [7.7 (1.7) vs 6.9 (1.0)%, P<0.01] of exercise training. Furthermore, exercise time and muscular strength were significantly improved after 4 weeks (P<0.01) as well as after 16 weeks (P<0.001) of training. Body mass and body-mass index, however, were not significantly altered throughout the study. The results indicated that a combined training program of strength and aerobic exercise could induce positive adaptations on glucose control, insulin action, muscular strength and exercise tolerance in women with type 2 diabetes.