The Role of Testosterone in Exercise-Induced Glycogen Supercompensation[*]

Abstract

Thirty-nine adult male guinea pigs, assigned to castratedsedentary, normal-sedentary, castrated-replacement-sedentary, castrated-trained, normal trained and castrated-replacement-trained treatment groups, were employed to assess the role of testosterone in exercise-induced glycogen supercompensation in skeletal muscle. Beginning on the seventh post-operative day, trained animals were run every other day for a total of ten trials, with trials one through five and trials six through ten being 30 and 40 min in duration, respectively. Forty-eight hours after the final exercise trial and 27 days after the onset of the experiment, the guinea pigs were killed and the vastus lateralis was rapidly removed for glycogen analysis. Normal-trained and castrated-replacement-trained treatment group glycogen means were significantly greater than those of castrated-trained and all sedentary treatment groups. The castrated-trained glycogen mean, which did not statistically differ from those of castrated-replacement-sedentary and normal-sedentary groups, was significantly greater than the glycogen mean of its sedentary counterpart. It was concluded that muscle glycogen levels are dependent on the chronic activity of the animal and this dependence is mediated in part through testosterone.

Key words

Exercise - Glycogen - Testosterone - Castration - Skeletal Muscle

1 This work was partially supported by the UCLA Academic Senate Committee on Research and by the Easter Seal Research Foundation of the National Easter Seal Society for Crippled Children and Adults, Inc.

1 This work was partially supported by the UCLA Academic Senate Committee on Research and by the Easter Seal Research Foundation of the National Easter Seal Society for Crippled Children and Adults, Inc.