Effects of Leg Exercise on Insulin Absorption in Diabetic Patients

Abstract

To examine the effects of leg exercise on insulin absorption from various injection sites, ¹²⁵I-labeled rapid-acting insulin (9 units) was injected subcutaneously into the leg, arm or abdomen of patients with insulin-dependent diabetes before one hour of intermittent leg (bicycle) exercise and on a resting, control day. Insulin disappearance from the leg increased by 135 per cent during the first 10 minutes of leg exercise (P<0.05) and remained 50 per cent above resting levels after 60 minutes (P<0.02). Leg exercise had no effect on insulin disappearance from the arm, but insulin disappearance from the abdomen was reduced during the post-exercise recovery period (P<0.02). As compared to leg injection, arm or abdominal injection reduced the hypoglycemic effect of exercise by 57 per cent (P<0.02) and 89 per cent (P<0.005), respectively.