| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Human Performance Laboratory, Ball State University, Muncie, Indiana
Submitted 23 May 2007 ; accepted in final form 16 July 2007
There is limited information on skeletal muscle properties in women with unloading and countermeasure programs to protect the unloading-induced atrophy. The current investigation tested the hypothesis that a concurrent aerobic and resistance exercise training program would preserve size and contractile function of slow- and fast-twitch muscle fibers. A secondary objective was to test the hypothesis that a leucine-enriched high-protein diet would partially attenuate single fiber characteristics. Vastus lateralis muscle biopsies were obtained before and on day 59 of bed rest from a control (BR; n = 8), nutrition (BRN; n = 8), or exercise (BRE; n = 8) group. Single muscle fibers were studied for diameter, peak force (Po), contractile velocity, and power. Those in the BR group had a decrease (P < 0.05) in myosin heavy chain (MHC) I diameter (–14%), Po (–35%), and power (–42%) and MHC IIa diameter (–16%) and Po (–31%; P = 0.06) and an increase (P < 0.05) in MHC hybrid fibers. Changes in size and function of MHC I (–19 to –44%) and IIa (–21% to –30%) fibers and MHC distribution in BRN individuals were similar to results in the BR group. In BRE conditions, MHC I and IIa size and contractile function were preserved during bed rest. These data show that the concurrent exercise program preserved the myocellular profile of the vastus lateralis muscle during 60-day bed rest. To combat muscle atrophy and function with long-term unloading, the exercise prescription program used in this study should be considered as a viable training program for the upper leg muscles, whereas the nutritional intervention used cannot be recommended as a countermeasure for skeletal muscle.
skeletal muscle; contractile properties; microgravity; spaceflight; WISE-2005 study
This article has been cited by other articles:
|
|
 |
|
  S. M. Phillips, E. I. Glover, and M. J. Rennie Alterations of protein turnover underlying disuse atrophy in human skeletal muscle J Appl Physiol, September 1, 2009; 107(3): 645 - 654. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Trudel, M. Payne, B. Madler, N. Ramachandran, M. Lecompte, C. Wade, G. Biolo, S. Blanc, R. Hughson, L. Bear, et al. Bone marrow fat accumulation after 60 days of bed rest persisted 1 year after activities were resumed along with hemopoietic stimulation: the Women International Space Simulation for Exploration study J Appl Physiol, August 1, 2009; 107(2): 540 - 548. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Trappe, D. Costill, P. Gallagher, A. Creer, J. R. Peters, H. Evans, D. A. Riley, and R. H. Fitts Exercise in space: human skeletal muscle after 6 months aboard the International Space Station J Appl Physiol, April 1, 2009; 106(4): 1159 - 1168. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Mounier, V. Tiffreau, V. Montel, B. Bastide, and L. Stevens Phenotypical transitions and Ca2+ activation properties in human muscle fibers: effects of a 60-day bed rest and countermeasures J Appl Physiol, April 1, 2009; 106(4): 1086 - 1099. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. P. Harber, J. D. Crane, J. M. Dickinson, B. Jemiolo, U. Raue, T. A. Trappe, and S. W. Trappe Protein synthesis and the expression of growth-related genes are altered by running in human vastus lateralis and soleus muscles Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2009; 296(3): R708 - R714. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Bergouignan, G. Trudel, C. Simon, A. Chopard, D. A. Schoeller, I. Momken, S. B. Votruba, M. Desage, G. C. Burdge, G. Gauquelin-Koch, et al. Physical Inactivity Differentially Alters Dietary Oleate and Palmitate Trafficking Diabetes, February 1, 2009; 58(2): 367 - 376. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. I. Glover, S. M. Phillips, B. R. Oates, J. E. Tang, M. A. Tarnopolsky, A. Selby, K. Smith, and M. J. Rennie Immobilization induces anabolic resistance in human myofibrillar protein synthesis with low and high dose amino acid infusion J. Physiol., December 15, 2008; 586(24): 6049 - 6061. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Luden, K. Minchev, E. Hayes, E. Louis, T. Trappe, and S. Trappe Human vastus lateralis and soleus muscles display divergent cellular contractile properties Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2008; 295(5): R1593 - R1598. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Tesch, F. von Walden, T. Gustafsson, R. M. Linnehan, and T. A. Trappe Skeletal muscle proteolysis in response to short-term unloading in humans J Appl Physiol, September 1, 2008; 105(3): 902 - 906. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Harber and S. Trappe Single muscle fiber contractile properties of young competitive distance runners J Appl Physiol, August 1, 2008; 105(2): 629 - 636. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Slivka, U. Raue, C. Hollon, K. Minchev, and S. Trappe Single muscle fiber adaptations to resistance training in old (>80 yr) men: evidence for limited skeletal muscle plasticity Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2008; 295(1): R273 - R280. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Bergouignan, D. A. Schoeller, S. Votruba, C. Simon, and S. Blanc The acetate recovery factor to correct tracer-derived dietary fat oxidation in humans Am J Physiol Endocrinol Metab, April 1, 2008; 294(4): E645 - E653. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
