Journal of Applied Physiology Track the topics, authors and articles important to you
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 83: 875-883, 1997;
8750-7587/97 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
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
Right arrow Citation Map
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 Fowler, M. D.
Right arrow Articles by Balaban, R. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fowler, M. D.
Right arrow Articles by Balaban, R. S.

Journal of Applied Physiology
Vol. 83, No. 3, pp. 875-883, September 1997
EXERCISE AND MUSCLE

Normalized metabolic stress for 31P-MR spectroscopy studies of human skeletal muscle: MVC vs. muscle volume

M. D. Fowler, T. W. Ryschon, R. E. Wysong, C. A. Combs, and R. S. Balaban

Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892

Received 16 July 1996; accepted in final form 6 June 1997.

Fowler, M. D., T. W. Ryschon, R. E. Wysong, C. A. Combs, and R. S. Balaban. Normalized metabolic stress for 31P-MR spectroscopy studies of human skeletal muscle: MVC vs. muscle volume. J. Appl. Physiol. 83(3): 875-883, 1997.---A critical requirement of submaximal exercise tests is the comparability of workload and associated metabolic stress between subjects. In this study, 31P-magnetic resonance spectroscopy was used to estimate metabolic strain in the soleus muscle during dynamic, submaximal plantar flexion in which target torque was 10 and 15% of a maximal voluntary contraction (MVC). In 10 healthy, normally active adults, (PCr + Pi)/PCr, where PCr is phosphocreatine, was highly correlated with power output normalized to the volume of muscle in the plantar flexor compartment (r = 0.89, P < 0.001). The same variable was also correlated, although less strongly (r = 0.78, P < 0.001), with power normalized to plantar flexor cross-sectional area. These findings suggest that comparable levels of metabolic strain can be obtained in subjects of different size when the power output, or stress, for dynamic plantar flexion is selected as a function of plantar flexor muscle volume. In contrast, selecting power output as a function of MVC resulted in a positive linear relationship between (PCr + Pi)/PCr and the torque produced, indicating that metabolic strain was increasing rather than achieving constancy as a function of MVC. These findings provide new insight into the design of dynamic muscle contraction protocols aimed at detecting metabolic differences between subjects of different body size but having similar blood flow capacity and mitochondrial volume per unit of muscle.

maximal voluntary contraction; soleus; magnetic resonance imaging; 4 tesla; creatine phosphate; adenosine 5'-triphosphate; phosphorus-31 magnetic resonance spectroscopy




This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
A. R. Barker, J. R. Welsman, J. Fulford, D. Welford, and N. Armstrong
Muscle phosphocreatine kinetics in children and adults at the onset and offset of moderate-intensity exercise
J Appl Physiol, August 1, 2008; 105(2): 446 - 456.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
C. A. Combs, A. H. Aletras, and R. S. Balaban
Effect of muscle action and metabolic strain on oxidative metabolic responses in human skeletal muscle
J Appl Physiol, November 1, 1999; 87(5): 1768 - 1775.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
M. T. GLADWIN, A. N. SCHECHTER, J. H. SHELHAMER, and F. P. OGNIBENE
The Acute Chest Syndrome in Sickle Cell Disease . Possible Role of Nitric Oxide in Its Pathophysiology and Treatment
Am. J. Respir. Crit. Care Med., May 1, 1999; 159(5): 1368 - 1376.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
C. Goreham, H. J. Green, M. Ball-Burnett, and D. Ranney
High-resistance training and muscle metabolism during prolonged exercise
Am J Physiol Endocrinol Metab, March 1, 1999; 276(3): E489 - E496.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online