Journal of Applied Physiology, Vol 69, Issue 3 1165-1170, Copyright © 1990 by American Physiological Society

ARTICLES

Metabolic effects of training in humans: a 31P-MRS study

J. A. Kent-Braun, K. K. McCully and B. Chance
Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia.

The purpose of this study was to determine the feasibility of measuring with 31P nuclear magnetic resonance the effects of an endurance training program on the high-energy phosphate metabolism of exercising human skeletal muscle. The system used included a 1.9-T 30-cm-bore Oxford Systems superconducting magnet, a PhosphoEnergetics spectrometer, and a modified Cybex isokinetic ergometer. Seven healthy human volunteers exercised their wrist flexor muscles 20 min/day 5 days/wk for 8 wk. Testing before and after the training period consisted of a performance test to measure muscle functional capacity and a ramp test to measure the work-energy cost relationship of the exercising muscles. The results indicate that the subjects had a significant increase in their work output on the 10-min performance test after training. They also exhibited an increase in the work-energy cost relationship on the ramp test as indicated by a decrease in peak Pi-to-phosphocreatine ratio and an increase in pH at the same relative power output after training. These results indicate that 1) the training program was sufficient to elicit a training effect and 2) this effect was observed with 31P nuclear magnetic resonance as an increased potential for oxidative metabolism, particularly at the high exercise levels.

This article has been cited by other articles:

				A. M. Jones, D. P. Wilkerson, N. J. Berger, and J. Fulford Influence of endurance training on muscle [PCr] kinetics during high-intensity exercise Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R392 - R401. [Abstract] [Full Text] [PDF]

				M. Roussel, J. P. Mattei, Y. Le Fur, B. Ghattas, P. J. Cozzone, and D. Bendahan Metabolic determinants of the onset of acidosis in exercising human muscle: a 31P-MRS study J Appl Physiol, March 1, 2003; 94(3): 1145 - 1152. [Abstract] [Full Text] [PDF]

				D Bendahan, J P Mattei, B Ghattas, S Confort-Gouny, M E Le Guern, and P J Cozzone Citrulline/malate promotes aerobic energy production in human exercising muscle Br. J. Sports Med., August 1, 2002; 36(4): 282 - 289. [Abstract] [Full Text] [PDF]

				C. S. Fulco, P. B. Rock, S. R. Muza, E. Lammi, B. Braun, A. Cymerman, L. G. Moore, and S. F. Lewis Gender alters impact of hypobaric hypoxia on adductor pollicis muscle performance J Appl Physiol, July 1, 2001; 91(1): 100 - 108. [Abstract] [Full Text] [PDF]

				L. J. Haseler, M. C. Hogan, and R. S. Richardson Skeletal muscle phosphocreatine recovery in exercise-trained humans is dependent on O2 availability J Appl Physiol, June 1, 1999; 86(6): 2013 - 2018. [Abstract] [Full Text] [PDF]

				A. Horska, L. J. Brant, D. K. Ingram, R. G. Hansford, G. S. Roth, and R. G. S. Spencer Effect of long-term caloric restriction and exercise on muscle bioenergetics and force development in rats Am J Physiol Endocrinol Metab, April 1, 1999; 276(4): E766 - E773. [Abstract] [Full Text] [PDF]

				S. A. Smith, S. J. Montain, R. P. Matott, G. P. Zientara, F. A. Jolesz, and R. A. Fielding Creatine supplementation and age influence muscle metabolism during exercise J Appl Physiol, October 1, 1998; 85(4): 1349 - 1356. [Abstract] [Full Text] [PDF]

				J. A. Kent-Braun, K. R. Sharma, R. G. Miller, and M. W. Weiner Effects of Electrically Stimulated Exercise Training on Muscle Function in Multiple Sclerosis Neurorehabil Neural Repair, January 1, 1996; 10(3): 143 - 151. [Abstract] [PDF]