Sports Med. 1991 Nov;12(5):313-25. Related Articles, Links
Protein intake and athletic performance.
Lemon PW, Proctor DN.
Applied Physiology Research Laboratory, School of Biomedical Sciences, Kent State University, Ohio.
For most of the current century, exercise/nutritional scientists have generally accepted the belief that exercise has little effect on protein/amino acid requirements. However, during the same time period many athletes (especially strength athletes) have routinely consumed diets high in protein. In recent years, the results of a number of investigations involving both strength and endurance athletes indicate that, in fact, exercise does increase protein/amino acid need. For endurance athletes, regular exercise may increase protein need by 50 to 100%. For strength athletes, the data are less clear; however, protein intakes in excess of sedentary needs may enhance muscle development. Despite these observations increased protein intake may not improve athletic performance because many athletes routinely consume 150 to 200% of sedentary protein requirements. Assuming total energy intake is sufficient to cover the high expenditures caused by daily training, a diet containing 12 to 15% of its energy from protein should be adequate for both types of athletes.
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http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1763249&dopt=Citation