Moderate Aerobic Exercise Has Little Effect On Insulin Sensitiv

Three months of moderate aerobic exercise did not improve insulin sensitivity in obese men with type 2 diabetes taking oral hypoglycemic agents. However, non-obese diabetics did show increased insulin sensitivity with exercise.

The study was conducted by investigators at the Quebec Heart Institute at Laval Hospital in Quebec City, Quebec, Canada. Six non-obese and seven obese men with type 2 diabetes treated with oral hypoglycemic agents participated in a 12-week ergocycle program at 60 percent VO2 peak for one hour a day, three times a week. Diet and medication were unchanged during the study. The investigators assessed insulin sensitivity using the euglycemic hyperinsulinemic clamp technique.

Aerobic exercise did result in an increased VO2 peak during the 12-week period. Considered as a single group, the patients showed no significant changes in fat mass, percent body fat, fasting plasma glucose and insulin levels, glycated hemoglobin levels or insulin sensitivity.

When investigators divided the patients into obese and non-obese groups, they found that only non-obese patients showed increased insulin sensitivity. No change was observed in the obese patients.

The investigators conclude that adiposity may be a determining factor in the metabolic benefits of exercise training in patients with type 2 diabetes. Med Sci Monit 2002; 8(2): CR59-65