Twice-weekly progressive resistance training decreases abdominal fat and improves insulin sensitivity in older men with type 2 diabetes.

OBJECTIVE To evaluate the influence of a twice-weekly progressive resistance training (PRT) program, without a concomitant weight loss diet, on abdominal fat and insulin sensitivity in older men with type 2 diabetes. RESEARCH DESIGN AND METHODS Nine older men (aged 66.6 +/- 3.1) with type 2 diabetes participated in a 16-week PRT supervised program (50-80% of the one repetition maximum), for all main muscle groups. Basal glycemia, HbA(1c), diet, habitual physical activity, body composition, and upper/lower maximal strength were measured. Insulin sensitivity was determined according to Bergman's minimal model procedure and abdominal fat was obtained by computed tomography. The measurements were taken 4 weeks before training (-4), immediately before training (0), and at 8-week intervals (i.e., weeks 8 and 16) during the 16-week training period. RESULTS No significant variation was observed in any of the above selected parameters during the 4-week control period. After PRT, both leg and arm maximal strength increased significantly by 17.1 and 18.2%, respectively. Visceral and subcutaneous abdominal fat decreased significantly by 10.3% (from 249.5 +/- 97.9 to 225.6 +/- 96.6 cm(3), P < 0.01) and by 11.2% (from 356.0 +/- 127.5 to 308.6 +/- 118.8 cm(3), P < 0.01), respectively, while no changes were observed in body mass. PRT significantly increased insulin sensitivity by 46.3% (from 2.0 +/- 1.2 to 2.8 +/- 1.6 . 10(4) . min(-1) . muU(-1) . ml(-1), P < 0.01), whereas it significantly decreased (-7.1%, P < 0.05) fasting blood glucose (from 146.6 +/- 28.3 to 135.0 +/- 29.3 mg/dl). Finally, a 15.5% increase in energy intake (from 2,287.1 +/- 354.7 to 2,619.0 +/- 472.1 kcal/day, P < 0.05) was observed. CONCLUSIONS Two sessions per week of PRT, without a concomitant weight loss diet, significantly improves insulin sensitivity and fasting glycemia and decreases abdominal fat in older men with type 2 diabetes.