Effects of physical training and diet therapy on carbohydrate metabolism in patients with glucose intolerance and non-insulin-dependent diabetes mellitus.

The effects of 12 wk of physical training in addition to hypocaloric diet (DPT group, N = 10) on body composition, carbohydrate (CHO) tolerance, and insulin secretion and action were compared with the effects of diet therapy alone (D group, N = 8) in CHO-intolerant and non-insulin-dependent diabetic subjects. Fat mass, fat-free mass (FFM), mean fasting plasma glucose, serum C-peptide, and insulin concentrations decreased similarly in both groups. The mean plasma glucose response to a mixed meal decreased approximately 20% in both treatment groups, and, after i.v. glucose, decreased 12% in the D group (P less than 0.05), but did not change in the DPT group (NS between groups). The acute serum insulin response (0-6 min) after IG increased significantly in the DPT group only (NS between groups). The mean basal endogenous glucose production (BEGP) decreased 17% (P less than 0.025) in the DPT group and by 31% (P less than 0.01) in the D group (NS between groups). Hepatic sensitivity to insulin, estimated by BEGP suppression during the euglycemic clamp, increased significantly by 25% in both groups. Total glucose disposal during the euglycemic clamp increased from 3.51 +/- 0.04 milligrams of glucose per kilogram of fat-free mass per minute (mg/kg-FFM/min) to 4.45 +/- 0.54 mg/kg-FFM/min (P less than 0.05) in the DPT group, but no change occurred in the D group (NS between groups).(ABSTRACT TRUNCATED AT 250 WORDS)