Interactions between dietary obesity and exercise-training on carbohydrate metabolism.
The present study addressed the important question of whether exercise-training could reduce insulin levels in exercise-trained rats made obese by a diet composed of palatable foods. Female rats were divided in exercise-trained or in sedentary groups which receive either a palatable high-energy diet or merely a standard laboratory chow. The high-energy diet was composed of supermarket foods including chocolate chips cookies, pop-corn, bologna, etc. Exercise-training program consisted of forced swimming, 6 d per week, 2 h per d, in water maintained at 36 degrees C. At the end of both fattening and exercise-training program, the animals were subjected to an intravenous glucose tolerance test. The results showed that high-energy diet and exercise-training had opposite effects on both glucose tolerance and insulin secretion: the former impaired glucose tolerance and increased insulin levels, whereas the latter leads to opposite adaptations. In addition, some abnormalities in insulin metabolism persisted in rats simultaneously assigned to exercise-training and high-energy diet. Thus, the present results also suggested that physical training alone could not reduce plasma insulin under control levels, and that a change in energy balance is possibly necessary to achieve this purpose.
D000273:Adipose Tissue / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D004032:Diet; D002149:Energy Intake; D005260:Female; D007328:Insulin / Q000097:blood*; D009765:Obesity / Q000209:etiology / Q000378:metabolism*; D005082:Physical Exertion; D051381:Rats; D011919:Rats, Inbred Strains
D001786:Blood Glucose; D007328:Insulin