Role of body fat loss in the exercise-induced improvement of the plasma lipid profile in non-insulin-dependent diabetes mellitus.

The study was designed to examine the impact of exercise training on the plasma lipid profile in non-insulin-dependent diabetes mellitus (NIDDM) and, more particularly, to determine the relationship between changes in body fat mass and changes in the lipid profile. Eleven men with NIDDM exercised for 1 hour thrice per week on an ergocycle over a 6-month period at 60% maximal oxygen uptake (Vo2max). Diet and hypoglycemic agents were kept constant throughout this period. Vo2max, body composition, fasting plasma glucose and insulin levels, glycosylated hemoglobin, and the lipid profile were determined at baseline, in the middle (3 months), and at the end (6 months) of the training program. When the subjects were considered as a group, the only significant effect of training was on Vo2max, which increased from 32.2 +/- 1.2 mL/kg/min at baseline to 38.0 +/- 1.7 mL/kg/min at 6 months (P < .001). When the data were analyzed on an individual basis, significant associations were observed between changes in body fat mass and changes in the low-density lipoprotein (LDL) cholesterol/high-density lipoprotein (HDL) cholesterol ratio (r = .62,P = .04) or triglyceride (TG) levels (r = .64,P = .03). These data indicate that fat loss, not training per se, favorably alters the lipid profile of subjects with NIDDM who participate in an aerobic physical-conditioning program.