|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
There are many factors that can influence glucose uptake by contracting skeletal muscle during exercise and although one may be intramuscular glycogen content, this relationship is at present not fully elucidated. To test the hypothesis that muscle glycogen concentration influences glucose uptake during exercise, 13 healthy men were studied during two series of experiments. Seven men completed 4 h of two-legged knee extensor exercise 16 h after reducing of muscle glycogen by completing 60 min of single-legged cycling (Series 1). A further six men completed 3 h of two-legged knee extensor exercise on two occasions: one after 60 min of two-legged cycling (16 h prior to the experimental trial) followed by a high carbohydrate diet (HCHO) and the other after the same exercise followed by a low carbohydrate diet (LCHO) (Series 2). Muscle glycogen was decreased by 40 % when comparing the pre-exercised leg (EL) with the control leg (CL) prior to exercise in Series 1. In addition, muscle glycogen was decreased by the same magnitude when comparing LCHO with HCHO in Series 2. In Series 1, glucose uptake was 3-fold higher in the first 60 min of exercise, in the presence of unchanged pre-exercise GLUT4 protein in EL compared with CL, suggesting that the lower glycogen, and not the exercise the day before, might have provided the stimulus for increased glucose uptake. Despite the same magnitude of difference in pre-exercise glycogen concentration when comparing Series 1 with Series 2, neither direct-nor isotopic tracer-determined glucose uptake was higher in LCHO compared with HCHO in Series 2. However, arterial concentrations of insulin and glucose were lower, while free fatty acids and adrenaline were higher in LCHO compared with HCHO. These data suggest that pre-exercise glycogen content may influence glucose uptake during subsequent exercise. However, this is only the case when delivery of substrates and hormones remains constant. When delivery of substrates and hormones is altered, the potential effect of glycogen on glucose uptake is negated.
This article has been cited by other articles:
![]() |
A Bassini-Cameron, A Monteiro, A Gomes, J P S Werneck-de-Castro, and L Cameron Glutamine protects against increases in blood ammonia in football players in an exercise intensity-dependent way Br. J. Sports Med., April 1, 2008; 42(4): 260 - 266. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Bruunsgaard Physical activity and modulation of systemic low-level inflammation J. Leukoc. Biol., October 1, 2005; 78(4): 819 - 835. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. K. Hansen, C. P. Fischer, P. Plomgaard, J. L. Andersen, B. Saltin, and B. K. Pedersen Skeletal muscle adaptation: training twice every second day vs. training once daily J Appl Physiol, January 1, 2005; 98(1): 93 - 99. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Arkinstall, C. R. Bruce, S. A. Clark, C. A. Rickards, L. M. Burke, and J. A. Hawley Regulation of fuel metabolism by preexercise muscle glycogen content and exercise intensity J Appl Physiol, December 1, 2004; 97(6): 2275 - 2283. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. T. Fueger, H. S. Hess, D. P. Bracy, R. R. Pencek, K. A. Posey, M. J. Charron, and D. H. Wasserman Regulation of Insulin-Stimulated Muscle Glucose Uptake in the Conscious Mouse: Role of Glucose Transport Is Dependent on Glucose Phosphorylation Capacity Endocrinology, November 1, 2004; 145(11): 4912 - 4916. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. J. Durham, S. L. Miller, C. W. Yeckel, D. L. Chinkes, K. D. Tipton, B. B. Rasmussen, and R. R. Wolfe Leg glucose and protein metabolism during an acute bout of resistance exercise in humans J Appl Physiol, October 1, 2004; 97(4): 1379 - 1386. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. K. Dalsgaard, S. Ogoh, E. A. Dawson, C. C. Yoshiga, B. Quistorff, and N. H. Secher Cerebral carbohydrate cost of physical exertion in humans Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2004; 287(3): R534 - R540. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Kristensen and T. Hansen Statistical analyses of repeated measures in physiological research: a tutorial Advan Physiol Educ, March 1, 2004; 28(1): 2 - 14. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. W. Wray, P. J. Fadel, M. L. Smith, P. Raven, and M. Sander Inhibition of {alpha}-adrenergic vasoconstriction in exercising human thigh muscles J. Physiol., March 1, 2004; 555(2): 545 - 563. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. V. Chakravarthy and F. W. Booth Eating, exercise, and "thrifty" genotypes: connecting the dots toward an evolutionary understanding of modern chronic diseases J Appl Physiol, January 1, 2004; 96(1): 3 - 10. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Watt, P. Krustrup, N. H. Secher, B. Saltin, B. K. Pedersen, and M. A. Febbraio Glucose ingestion blunts hormone-sensitive lipase activity in contracting human skeletal muscle Am J Physiol Endocrinol Metab, January 1, 2004; 286(1): E144 - E150. [Abstract] [Full Text] |
||||
![]() |
G. van Hall, A. Steensberg, M. Sacchetti, C. Fischer, C. Keller, P. Schjerling, N. Hiscock, K. Moller, B. Saltin, M. A. Febbraio, et al. Interleukin-6 Stimulates Lipolysis and Fat Oxidation in Humans J. Clin. Endocrinol. Metab., July 1, 2003; 88(7): 3005 - 3010. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |