Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

J Appl Physiol (June 14, 2007). doi:10.1152/japplphysiol.00195.2007
This Article
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
103/3/903    most recent
00195.2007v1
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Fujita, S.
Right arrow Articles by Rasmussen, B. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fujita, S.
Right arrow Articles by Rasmussen, B. B.
Submitted on February 16, 2007
Accepted on June 11, 2007

Blood Flow Restriction during Low-Intensity Resistance Exercise Increases S6K1 Phosphorylation and Muscle Protein Synthesis

Satoshi Fujita1*, Takashi Abe2, Micah J. Drummond3, Jerson G. Cadenas4, Hans C. Dreyer3, Yoshiaki Sato2, Elena Volpi5, and Blake B. Rasmussen3

1 Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States; Human and Engineered Environment, Graduate School of Frontier Sciences, University of Tokyo, Tokyo, Texas, Japan
2 Human and Engineered Environment, Graduate School of Frontier Sciences, University of Tokyo, Tokyo, Japan
3 Physical Therapy, University of Texas Medical Branch, Galveston, Texas, United States
4 Internal Medicine, University of Texas Medical Branch, Galveston, Texas, United States
5 Internal Medicine - Geriatrics, University of Texas Medical Branch, Galveston, Texas, United States

* To whom correspondence should be addressed. E-mail: safujita{at}gmail.com.

Low-intensity resistance exercise training combined with blood flow restriction (REFR) increases muscle size and strength as much as conventional resistance exercise with high-loads. However, the cellular mechanism(s) underlying the hypertrophy and strength gains induced by REFR are unknown. We have recently shown that the mTOR signaling pathway is involved in the increase in muscle protein synthesis after an acute bout of high-intensity resistance exercise in humans. Therefore, we hypothesized that an acute bout of REFR would enhance mTOR signaling and stimulate muscle protein synthesis (MPS). We measured MPS and phosphorylation status of mTOR-associated signaling proteins in 6 young male subjects. Subjects were studied once during blood flow restriction (REFR, bilateral leg extension exercise at 20% of 1-RM while a pressure cuff was placed on the proximal end of both thighs and inflated at 200mmHg) and a second time using the same exercise protocol but without the pressure cuff (CTRL). MPS in the vastus lateralis muscle was measured by using stable isotope techniques and the phosphorylation status of signaling proteins were determined by immunoblotting. Blood lactate, cortisol, and growth hormone were higher following REFR as compared to CTRL (P<0.05). S6K1 phosphorylation, a downstream target of mTOR, increased concurrently with a decreased eEF2 phosphorylation and a 46% increase in MPS following REFR (P<0.05). MPS and S6K1 phosphorylation were unchanged in the CTRL group post-exercise. We conclude that the activation of the mTOR signaling pathway appears to be an important cellular mechanism which may help explain the enhanced muscle protein synthesis during REFR.




This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
N. A. Burd, J. E. Tang, D. R. Moore, and S. M. Phillips
Exercise training and protein metabolism: influences of contraction, protein intake, and sex-based differences
J Appl Physiol, May 1, 2009; 106(5): 1692 - 1701.
[Abstract] [Full Text] [PDF]

Home page
 J. Nutr.Home page
N. K. McGhee, L. S. Jefferson, and S. R. Kimball
Elevated Corticosterone Associated with Food Deprivation Upregulates Expression in Rat Skeletal Muscle of the mTORC1 Repressor, REDD1
J. Nutr., May 1, 2009; 139(5): 828 - 834.
[Abstract] [Full Text] [PDF]

Home page
 Biol Res NursHome page
S. Al-Majid and D. P. Gray
A Biobehavioral Model for the Study of Exercise Interventions in Cancer-related Fatigue
Biol Res Nurs, April 1, 2009; 10(4): 381 - 391.
[Abstract] [PDF]

Home page
 J. Appl. Physiol.Home page
T. Suga, K. Okita, N. Morita, T. Yokota, K. Hirabayashi, M. Horiuchi, S. Takada, T. Takahashi, M. Omokawa, S. Kinugawa, et al.
Intramuscular metabolism during low-intensity resistance exercise with blood flow restriction
J Appl Physiol, April 1, 2009; 106(4): 1119 - 1124.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
D. R. Moore and N. A. Burd
Exercise intensity matters for both young and old muscles
J. Physiol., February 1, 2009; 587(3): 511 - 512.
[Full Text] [PDF]

Home page
 J. Physiol.Home page
S. B. Wilkinson, S. M. Phillips, P. J. Atherton, R. Patel, K. E. Yarasheski, M. A. Tarnopolsky, and M. J. Rennie
Differential effects of resistance and endurance exercise in the fed state on signalling molecule phosphorylation and protein synthesis in human muscle
J. Physiol., August 1, 2008; 586(15): 3701 - 3717.
[Abstract] [Full Text] [PDF]

Home page
 Biol Res NursHome page
S. Al-Majid and H. Waters
The biological mechanisms of cancer-related skeletal muscle wasting: the role of progressive resistance exercise.
Biol Res Nurs, July 1, 2008; 10(1): 7 - 20.
[Abstract] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 1948 by the American Physiological Society.