title: Failure of weight training to affect urinary indices of protein metabolism in men.
abstract: It is commonly believed by some athletes that strength building exercise "tears down" skeletal muscle tissue, thereby enhancing the dietary need for protein, but this has not been demonstrated. Ten college-age males served as subjects in a 15-d, controlled feeding study. The men were 23.1 +/- 2.2 yr old (mean +/- SD), 177 +/- 5 cm in height, and 71.7 +/- 9.1 kg in body weight (study days = 1 to 15). The lacto-ovo-vegetarian diet provided 0.9 g/kg protein and 15.1 +/- 0.4 MJ (3,604 +/- 104 kcal) . d-1 energy (study days = 6 to 15). On days 8 and 12, subjects participated in a standardized strength building, weight training exercise regimen. Post-exercise days 9 to 11 and 13 to 15 were designated for recovery. Daily (24-h) urine collections were analyzed for ammonia, creatinine, 3-methylhistidine, total nitrogen, and urea. There was no acute (24-h) effect of weight training exercise on any excretion levels. In particular, urinary 3-methylhistidine excretion data indicate that skeletal muscle protein catabolism was not changed by isolated bouts of weight training exercise.
mesh_terms: D000328:Adult; D000641:Ammonia / Q000652:urine; D003404:Creatinine / Q000652:urine; D006801:Humans; D008297:Male; D008762:Methylhistidines / Q000652:urine; D009584:Nitrogen / Q000378:metabolism; D011507:Proteinuria; D013177:Sports; D014508:Urea / Q000652:urine; D014891:Weight Lifting
chemical_list: D008762:Methylhistidines; D000641:Ammonia; D014508:Urea; D003404:Creatinine; C028118:3-methylhistidine; D009584:Nitrogen