Effects of acute exercise on insulin binding to monocytes in obesity.

The effect of 3 hr of cycle erogmeter exercise on 125I-insulin binding to monocytes was studied in obese and 10 nonobese control subjects. In the basal state before exercise, total specific 125I-insulin binding to monocytes in obese subjects (4.8% +/- 0.3%) was 25% lower than in control subjects (6.6% +/- 0.4%, p less than 0.01). During exercise, insulin binding increased in both groups (p less than 0.05), but the rise in obese subjects was minimal (13% +/- 1%) and was 60%--70% lower than in controls (36% +/- 3%, p less than 0.01). The data indicate that the increment in insulin binding to monocytes induced by acute exercise is diminished in obesity.