Abstract: Objective To observe the effects of exercise on food intake and body composition in obesity-prone and obesity-resistant rats, in order to provide experimental evidence for fitness and exercise for weight loss. Methods Seventy male SD rats were fed with high-fat diet or normal diet, after 8 weeks, obesity-prone and obesity-resistant rats were screened out based on body weight; then they were divided into four groups: obesity-prone quiet group (OP), obesity-prone exercise group (OPE), obesity-resistant quiet group (OR) and obesity-resistant exercise group (ORE), and all animals were continued to be given high-fat diet, the exercise groups were arranged to adaptive exercise for one week, then were performed eight weeks treadmill exercise, and the body composition of rats were measured using the Prodigy dual-energy X-ray absorptiometry. Results (1) Compared with the quiet groups, food intake in the exercise groups were decreased significantly; (2) Compared with the quiet groups, body weight and fat tissue in the exercise groups were significantly decreased, the amount of muscle tissue of rats in OPE group were significantly increased, and the amount of muscle tissue of rats in ORE group were not changed significantly. Conclusion The same intensity exercise can produce different effects on the amount of muscle tissue in obesity-prone and obesity-resistant rats, it is necessary to fully take the intensity and nutritional supplements into account when exercise used for fitness.

Key words: Exercise, Obesity-prone, Obesity-resistant, Food intake, Body composition