Effect of exercise and recovery on muscle protein synthesis in human subjects

Journal Article · Mon Oct 01 04:00:00 EDT 1990 · American Journal of Physiology; (USA)

OSTI ID:6323886

Carraro, F; Stuart, C A; Hartl, W H; Rosenblatt, J; Wolfe, R R ^[1]

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1. Shriners Burns Institute, Galveston, TX (USA)

Previous studies using indirect means to assess the response of protein metabolism to exercise have led to conflicting conclusions. Therefore, in this study we have measured the rate of muscle protein synthesis in normal volunteers at rest, at the end of 4 h of aerobic exercise (40% maximal O2 consumption), and after 4 h of recovery by determining directly the rate of incorporation of 1,2-(13C)leucine into muscle. The rate of muscle protein breakdown was assessed by 3-methylhistidine (3-MH) excretion, and total urinary nitrogen excretion was also measured. There was an insignificant increase in 3-MH excretion in exercise of 37% and a significant increase (P less than 0.05) of 85% during 4 h of recovery from exercise (0.079 +/- 0.008 vs. 0.147 +/- 0.0338 mumol.kg-1.min-1 for rest and recovery from exercise, respectively). Nonetheless, there was no effect of exercise on total nitrogen excretion. Muscle fractional synthetic rate was not different in the exercise vs. the control group at the end of exercise (0.0417 +/- 0.004 vs. 0.0477 +/- 0.010%/h for exercise vs. control), but there was a significant increase in fractional synthetic rate in the exercise group during the recovery period (0.0821 +/- 0.006 vs. 0.0654 +/- 0.012%/h for exercise vs. control, P less than 0.05). Thus we conclude that although aerobic exercise may stimulate muscle protein breakdown, this does not result in a significant depletion of muscle mass because muscle protein synthesis is stimulated in recovery.

• OSTI ID: 6323886
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 259:4 Pt 1; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
AZOLES
BIOLOGICAL EFFECTS
BIOSYNTHESIS
CARBON 13
CARBON ISOTOPES
CARBOXYLIC ACIDS
EVEN-ODD NUCLEI
EXERCISE
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HISTIDINE
HYDROGEN COMPOUNDS
IMIDAZOLES
ISOTOPE APPLICATIONS
ISOTOPES
LEUCINE
LIGHT NUCLEI
METABOLISM
MUSCLES
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROTEINS
STABLE ISOTOPES
SYNTHESIS
TRACER TECHNIQUES
TRITIUM COMPOUNDS