A test of the carbon-nitrogen balance technique to measure body composition of exercising animals

Four randomly selected male Wistar rats were placed in separate metabolic chambers containing torqued Wahmann activity wheels. Quantitative collection of expired CO 2, feces, and urine were carried out and the Carbon-Nitrogen balance technique was used to determine the changes in body composition of exercised animals during sequential, 48-hour periods. The behavioral contigency significantly increased running performance and weight gain. The weight of all body compartments, with the exception of body fat, increased significantly. Increased exercise significantly increased heat production. Sufficient data were gathered to permit discussion of individual animals and their adaptations and responses to the running contingencies.