TREADMILL TRAINING IMPROVES INTRAVENOUS GLUCOSE-TOLERANCE AND INSULIN SENSITIVITY IN FATTY ZUCKER RATS

The effect of treadmill training on i.v. glucose tolerance and insulin sensitivity was investigated in Zucker rats (fafa). In 25-wk-old fafa animals with the typical metabolic syndrome of massive obesity, glucose intolerance, hypertriglyceridemia and insulin resistance, treadmill exercise of only very mild intensity was carried out for 6 wk. The training program induced a marked reduction in basal and post-glucose challenge plasma insulin levels and a slight but significant improvement of i.v. glucose tolerance. No alteration in insulin sensitivity of the isolated perfused hindquarter was demonstrable. In another study a 9-wk training program was started in 7-wk-old fafa rats before the development of their metabolic syndrome. In the sedentary control animals glucose intolerance and insulin resistance developed during the study period; in the training group, both the deterioration of glucose tolerance and the decrease of insulin sensitivity were prevented. In fafa rats the following was demonstrated: in young animals physical training may prevent a genetically predisposed deterioration of glucose tolerance and insulin sensitivity; and in adult animals mild physical training may improve i.v. glucose tolerance and insulin sensitivity.