Protein acute exercise effects

Exercise is known to have acute catabolic effects on muscle protein turnover. During exercise protein snythesis is depressed which leads to protein catabolism. However, the impact of a relatively short exercise bout on 24-hour protein needs is unclear. Anaerobic exercise can produce hypertrophy of specific muscles depending on the type of training utilized. The hypertrophy is due to a positive balance in protein turnover which appears to be produced by an increase in the rate of protein synthesis after exercise. The increased need for protein during anaerobic exercise is unlikely to be more than 7 grams per day. 

Williamson D, Gallagher P, Barber M et al. (2003) Mitogen-activated protein kinase (MAPK) pathway activation effects of age and acute exercise on human skeletal muscle. J Physiol 547, 977-987. 

The impact of aerobic exercise on protein requirements remains uncertain. Exercise clearly can disrupt protein metabolism, both protein turnover and amino acid oxidation. However, it remains to be determined if these effects are acute effects of exhaustive exercise or if moderate exercise in trained individuals still produces increased oxidation of amino acids. 

To determine whether 4-hydroxynonenal could account for the acute effects of ozone on human alveolar macrophages, Hamilton jr. et al. (1998) exposed healthy, non-smoking volunteers to 0.4 ppm ozone or air for 1 h with exercise (each subject served as his/her own control). Six hours after ozone exposure, cells obtained by airway lavage were examined for apoptotic cell injury, presence of 4-hydroxynonenal adducts, and expression of stress proteins. Significant apoptosis was evident in airway lung cells after ozone exposure. Western analysis demonstrated an increase in a 32-kDa 4-hydroxynonenal protein adduct and a number of stress proteins, viz., 72-kDa heat shock protein and ferritin, in alveolar macrophages after ozone exposure. All these effects could be replicated by in vitro exposure of alveolar macrophages to 4-hydroxy-nonenal. 

Yarasheski KB, Zachwieja JJ, Bier DM. (1993) Acute effects of resistance exercise on muscle protein synthesis rate in young and elderly men and women. Am J Physiol Endocrinol Metab 265, B210-B214. 

In contrast to endurance exercise, acute whole-body resistance exercise does not alter leucine oxidation. In this same study we also did not find an effect of acute resistance exercise on whole-body protein synthesis, either during exerdse or for up to 2 h post-exerdse. We hypothesized that since muscle protein synthesis (MPS) accounted for only 25% of whole-body synthesis, changes in MPS either may be not measurable or would be negated by a redprocal change in the synthesis of another protein, such as one in the gastrointestinal tract. 

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