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


     

J Appl Physiol (July 30, 2004). doi:10.1152/japplphysiol.00421.2004
This Article
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
97/6/2275    most recent
00421.2004v1
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 Arkinstall, M. J
Right arrow Articles by Hawley, J. A
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Arkinstall, M. J
Right arrow Articles by Hawley, J. A
Submitted on April 21, 2004
Accepted on July 22, 2004

REGULATION OF FUEL METABOLISM BY PRE-EXERCISE MUSCLE GLYCOGEN CONTENT AND EXERCISE INTENSITY

Melissa J Arkinstall1, Clinton R Bruce1, Sally A Clark1, Caroline C Rickards1, Louise M Burke1, and John A Hawley1*

1 School of Medical Sciences, RMIT University, Bundoora, VIC, Australia; School of Health Sciences, Deakin University, Burwood, VIC, Australia

* To whom correspondence should be addressed. E-mail: john.hawley{at}rmit.edu.au.

To date the results of studies that have examined the effects of altering pre-exercise muscle glycogen content and exercise intensity on endogenous carbohydrate oxidation are equivocal. Differences in the training status of subjects between investigations may, in part, explain these inconsistent findings. Accordingly, we determined the relative effects of exercise intensity and carbohydrate availability on patterns of fuel utilization in the same subjects who performed a random order of four 60 min rides, two at 45% and two at 70% of VO2peak, after exercise-diet intervention to manipulate muscle glycogen content. Pre-exercise muscle glycogen content was 596 ± 43 and 202 ±21 mmol/kg d.m. (P <0.001) for high (HG) and low (LG) conditions respectively. RER was higher for HG than LG during exercise at both 45% (0.85 ±0.01 vs. 0.74 ±0.01; P <0.001) and 70% of VO2peak (0.90 ±0.01 vs. 0.79 ±0.01; P <0.001). The contribution of whole body muscle glycogen oxidation to energy expenditure differed between LG and HG for exercise at both 45% (5 ±2% vs. 45 ±5%; P <0.001) and 70% (25 ±3% vs. 60 ±3%; P <0.001) of VO2peak. Yet despite marked differences in pre-exercise muscle glycogen content and its subsequent utilization, rates of plasma glucose Rd were similar under all conditions. We conclude that in moderately-trained individuals, muscle glycogen availability (low vs. high) does not influence rates of plasma glucose disposal during either low- or moderate-intensity exercise.




This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
A. Vol, O. Gribova, S. Berman, Y. Siman-Tov, and S. Efrati
Application of muscle biopotential measurement for sustained, noninvasive blood glucose survey
J Appl Physiol, July 1, 2009; 107(1): 253 - 260.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
P. Puthanveetil, F. Wang, G. Kewalramani, M. S. Kim, E. Hosseini-Beheshti, N. Ng, W. Lau, T. Pulinilkunnil, M. Allard, A. Abrahani, et al.
Cardiac glycogen accumulation after dexamethasone is regulated by AMPK
Am J Physiol Heart Circ Physiol, October 1, 2008; 295(4): H1753 - H1762.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
K. De Bock, W. Derave, B. O. Eijnde, M. K. Hesselink, E. Koninckx, A. J. Rose, P. Schrauwen, A. Bonen, E. A. Richter, and P. Hespel
Effect of training in the fasted state on metabolic responses during exercise with carbohydrate intake
J Appl Physiol, April 1, 2008; 104(4): 1045 - 1055.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
C. C. Greenberg, M. J. Jurczak, A. M. Danos, and M. J. Brady
Glycogen branches out: new perspectives on the role of glycogen metabolism in the integration of metabolic pathways
Am J Physiol Endocrinol Metab, July 1, 2006; 291(1): E1 - E8.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 1966 by the American Physiological Society.