n e t t @ v i s i o n . e r i . h a rv a rd . e d u .

Eight insulin-dependent adolescents (4 boys, 4 girls) participated in an 8-wk program of supervised exercise, and 8 matched controls were encouraged to exercise on their own without supervision. All 16 subjects were asked to follow a standard ADA diet plan, kept a self-reported log of caloric intake, and met with a dietitian weekly to review their diets. Exercise for the supervised subjects was scheduled between the routine afternoon snack and the evening meal, and subjects were asked not to consume additional food on exercise days. After the 8-wk program, glycemic control, as measured by glycosylated serum albumin and blood glucose values (but not by glycosylated hemoglobin), improved in the supervised-exercise group despite reduced daily insulin dosage. Cardiorespiratory fitness, as measured by voluntary maximum treadmill time (Bruce protocol) and submaximal exercise heart rates, also improved. No changes were observed in the unsupervised control group.