Exercise training decreases body fat more in self-selecting than in chow-fed rats.
This study was designed to examine the influence of exercise training on body weight gain and feeding pattern in rats placed on a self-selection or a chow diet regimen. Adult, male, Wistar rats were submitted to daily 2-h treadmill exercise for 28 days (about 50% of VO2 max) at the beginning of the nocturnal period. Two other groups of rats were examined during the same time: a sedentary group that was deprived of food and water during the training session and a control group without any treatment. Food intakes were continuously recorded. For both feeding regimens, trained rats, relative to their respective controls, showed at the end of the experiment a reduction in body weight gain due to a reduced body fat deposit. Moreover, white adipose tissue (WAT) mass of self-selecting rats was smaller than in chow-fed rats. Exercise training decreased plasma glucose level in chow-fed rats and plasma insulin level in self-selecting rats. In self-selecting rats, food intake was slightly increased due to enhanced protein intake during the nocturnal period and fat intake increased both during the nighttime and daytime periods, whereas in chow-fed rats, food intake was decreased during the daytime period. These results show that, in rats placed on a self-selection regimen, exercise training increased fat consumption but reduced WAT. This could be a consequence of an increased lipolytic capacity of adipocytes in self-selecting trained rats. Thus, it appears from these results that the diet's carbohydrate-to-fat ratio can be an important parameter in shaping the interaction between exercise and body weight.
Rieth
N
N
GER Biologie et Nutrition Humaine, INA-PG, Paris, France.
Larue-Achagiotis
C
C
D000273:Adipose Tissue / Q000502:physiology*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000502:physiology*; D004032:Diet; D002149:Energy Intake / Q000502:physiology; D005502:Food; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
D001786:Blood Glucose; D007328:Insulin