| Autor: |
Jim R. Potvin, Jonathan P. Little, Joshua G. A. Cashaback, Martin J. Gibala, Amy J. Hector, Stuart M. Phillips, Nicholas A. Burd, Daniel W. D. West, Andrew J. R. Cochran, Richard Andrews, Steven K. Baker |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
The Journal of Physiology. 590:351-362 |
| ISSN: |
0022-3751 |
| Popis: |
report that leg extension exercise at 30% of the best effort (which is a load that is comparatively light), with a slow lifting movement (6 s up and 6 s down) performed to fatigue produces greater increases in rates of muscle protein synthesis than the same movement performed rapidly (1 s up and 1 s down). These results suggest that the time the muscle is under tension during exercise may be important in optimizing muscle growth; this understandingenables us to better prescribe exercise to those wishing to build bigger muscles and/or to prevent muscle loss that occurs with ageing or disease. Abstract We aimed to determine if the time that muscle is under loaded tension during low intensity resistance exercise affects the synthesis of specific muscle protein fractions or phosphorylation of anabolic signalling proteins. Eight men (24 ±1years (SEM), BMI =26.5 ±1.0 kgm −2 ) performed three sets of unilateral knee extension exercise at 30% of one-repetition maximum strength involving concentric and eccentric actions that were 6 s in duration to failure (SLOW) or a work-matched bout that consisted of concentric and eccentric actions that were 1 s in duration (CTL). Participants ingested 20 g of whey protein immediately after exercise and again at 24 h recovery. Needle biopsies (vastus lateralis) were obtained while fasted at rest and after 6, 24 and 30h post-exercise in the fed-state following a primed, constant infusion of L-(ring- 13 C6)phenylalanine. Myofibrillar protein synthetic rate was higher in the SLOW condition versus CTL after 24-30 h recovery (P |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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