| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Departments of Neuroscience and Anesthesiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07107-3000; 3 Departments of Medicine and Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033; and 2 Department of Exercise Science, University of Georgia, Athens, Georgia 30602-6554
The purpose of this experiment was to examine the effects of the endogenous opioid system on forearm muscle pain and muscle sympathetic nerve activity (MSNA) during dynamic fatiguing exercise. Twelve college-age men (24 ± 4 yr) performed graded (1-min stages; 30 contractions/min) handgrip to fatigue 1 h after the ingestion of either 60 mg codeine, 50 mg naltrexone, or placebo. Pain (0-10 scale) and exertion (0-10 and 6-20 scales) intensities were measured during the last 15 s of each minute of exercise and every 15 s during recovery. MSNA was measured continuously from the peroneal nerve in the left leg. Pain threshold occurred earlier [1.8 ± 1, 2.2 ± 1, 2.2 ± 1 J: codeine, naltrexone, and placebo, respectively] and was associated with a lower rating of perceived exertion (RPE) (2.7 ± 2, 3.6 ± 2, 3.8 ± 2: codeine, naltrexone, and placebo, respectively) in the codeine condition compared with either the naltrexone or placebo conditions. There were no main effects (i.e., drugs) or interaction (i.e., drugs × time) for either forearm muscle pain or RPE during exercise [pain: F (2, 22) = 0.69, P = 0.51]. There was no effect of drug on MSNA, heart rate, or blood pressure during baseline, exercise, or recovery. Peak exercise MSNA responses were 21 ± 1, 21 ± 2.0, and 21 ± 2.0 bursts/30 s for codeine, naltrexone, and placebo conditions, respectively. Peak mean arterial pressure responses were 135 ± 4, 131 ± 3, and 132 ± 4 mmHg for codeine, naltrexone, and placebo conditions, respectively. It is concluded that neither 60 mg codeine nor 50 mg naltrexone has an effect on forearm muscle pain, exertion, or MSNA during high- intensity handgrip to fatigue.
codeine; rating of perceived exertion; pain perception; autonomic nervous system
This article has been cited by other articles:
|
|
 |
|
  C. A. Ray and J. R. Carter Central modulation of exercise-induced muscle pain in humans J. Physiol., November 15, 2007; 585(1): 287 - 294. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. Ray and K. D. Monahan Aging, opioid-receptor agonists and antagonists, and the vestibulosympathetic reflex in humans J Appl Physiol, May 1, 2004; 96(5): 1761 - 1766. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Carter, C. L. Sauder, and C. A. Ray Effect of morphine on sympathetic nerve activity in humans J Appl Physiol, November 1, 2002; 93(5): 1764 - 1769. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. L. Wasmund, E. C. Westerholm, D. E. Watenpaugh, S. L. Wasmund, and M. L. Smith Interactive effects of mental and physical stress on cardiovascular control J Appl Physiol, May 1, 2002; 92(5): 1828 - 1834. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Derchak, A. W. Sheel, B. J. Morgan, and J. A. Dempsey Effects of expiratory muscle work on muscle sympathetic nerve activity J Appl Physiol, April 1, 2002; 92(4): 1539 - 1552. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
