Abstract
The effects of voluntary exercise on serum lipids, weight and glycogen content of the gastrocnemius muscle and body composition of rats fed different kinds of dietary protein were investigated. Exercise training and sedentary rats were fed a diet consisting of 25% protein, 5% fat and 65% carbohydrate for 5 weeks. The sources of the protein were varied and casein, gluten or soy protein isolate (soy protein) was given as a source of dietary protein. The rats fed the casein diet showed higher levels of serum total cholesterol and triglyceride than those fed the gluten or the soy protein diet in sedentary groups. Exercise lowered serum lipids. The effect of exercise on serum lipids was clearly noticed in rats fed the casein diet. Exercise training rats fed the casein diet showed higher levels in weight and glycogen content of gastrocnemius muscle than sedentary ones. Exercise lowered significantly body fat levels in rats fed the casein or the soy protein diet but it was not so effective in rats fed the gluten diet. These data suggested that the exercise-induced metabolic responses were greatly affected by the dietary protein source.
