Metabolic effects of the addition of resistive to aerobic exercise in older men

The metabolic changes associated with the addition of 4 months of resistive exercise to an existing aerobic exercise program (AEX+RT, n = 7) were compared to a maintenance aerobic exercise program (AEX, n = 8) in overweight, older men. The subjects in this study had recently completed a 6-month aerobic exercise program (treadmill walking, 45 min/d, 2 d/wk). The AEX+RT group added 6 exercises on upper- and lower-body pneumatic-resistance machines (2 sets, 15 repetitions each, 2 d/wk) to an aerobic exercise program at > or = 70% heart rate reserve for 30-40 min, 2 d/wk on treadmill, while the AEX group continued the same maintenance treadmill AEX program. There were no baseline differences in body weight, VO2max, or glucose metabolism between groups. The AEX+RT group increased upper- and lower-extremity strength by 28 +/- 4% and 46 +/- 6%, respectively (p < .05), despite a 9% decrease in VO2max (p < .05). VO2max did not change in the AEX group. There was no change in the fasting glucose or insulin levels, or the 3-h glucose responses to an oral glucose load in either group. The insulin responses decreased by 25 +/- 4% in the AEX+RT group (p < .01) but did not change in the AEX group. In conclusion, the addition of resistive exercise training to an existing aerobic exercise program may improve insulin sensitivity in overweight, older men, and thus prevent the development of type 2 diabetes.