VOLUNTARY EXERCISE IMPROVES GLYCEMIA IN NONOBESE DIABETIC (NOD) MICE

The non-obese diabetic (NOD) mouse was used to investigate the effects of voluntary wheel running exercise on blood glucose levels, glycosyl ated hemoglobin, and longevity in Type 1 diabetes mellitus. In Experim ent 1, diabetic and normoglycemic mice exercised 5 h/day, 5 days/week for 3 weeks matched with non-exercising controls. In diabetic animals a positive correlation was found between blood glucose and the number of revolutions performed (P less-than-or-equal-to 0.02). Exercise also significantly lowered blood glucose between baseline and post-exercis e in both diabetic and normoglycemic animals. In Experiment 2, mice ex ercised 2 h/day, 5 days/week. For the diabetic animals, glycosylated h emoglobin was lower than that of matched non-exercising diabetic anima ls at week 3 (11.1 +/- 0.6% vs. 15.0 +/- 1.6%, P < 0.001). Diabetic ru nners were able to train and significantly increased running in the fi rst 4 weeks (P < 0.05). At the end of 9 weeks all 5 diabetic runners w ere alive, compared with 3 of 5 non-running diabetic animals. We concl ude: (i) the NOD mouse is a useful model for the study of exercise in Type 1 diabetes, (ii) running exercise is associated with a drop in bl ood glucose, (iii) the amount of voluntary exercise performed correlat es with blood glucose in diabetic animals, and (iv) diabetic mice will increase running distance in the first few weeks after diagnosis.