Meal-feeding and physical effort. 1. Metabolic changes induced by exercise training.
To evaluate the consequences of the combination of meal-feeding (which causes in the long term several adaptations that lead to saving stored energetic substrates), rats subjected to a 2-hr feeding/22-hr fasting schedule were forced to swim 30 min everyday at a fixed hour during four weeks. The results indicate that meal-fed exercised rats: 1) increase food intake above that found in the nonexercising and the corresponding (nonfood-restricted) controls; 2) did not lose weight (in contrast to the controls); 3) initially had a high glycogen mobilization but at the end of the fourth week started to save hepatic glycogen again, despite the intense energy demanding exercise; 4) maintained a slight hyperglycemia; 5) mobilized less free fatty acids than the nonexercising meal-fed rats, probably due to higher insulinemia; 6) had a lower content of ascorbic acid in the adrenal glands in comparison to the control exercising rats; this suggests that the exercise was less stressful in the latter group.
Curi
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Department of Physiology and Biophysics, University of São Paulo, Brazil.
Hell
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Timo-Iaria
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D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D004734:Energy Metabolism / Q000502:physiology*; D005227:Fatty Acids / Q000378:metabolism; D005247:Feeding Behavior / Q000502:physiology*; D007328:Insulin / Q000097:blood; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D010805:Physical Conditioning, Animal; D051381:Rats; D011919:Rats, Inbred Strains; D015430:Weight Gain / Q000502:physiology
D001786:Blood Glucose; D005227:Fatty Acids; D007328:Insulin; D008112:Liver Glycogen