Prolonged submaximal eccentric exercise is associated with increased levels of plasma il-6. Rohde, Thomas, Dave A. Maclean, Erik A. Richter, Bente Kiens, and Bente Klarlund Pedersen. The Copenhagen Muscle Research Centre, Department of Infectious Diseases, Rigshospitalet, University Hospital, Copenhagen and August Krogh Institute, University of Copenhagen, Denmark
APStracts 4:0066E, 1997.
To study the relationship between exercise-related muscle proteolysis and the cytokine response, a prolonged one legged eccentric exercise model was used. Subjects performed two trials (a branched chain amino acid (BCAA) supplementation and a control trial). The release of amino acids from muscle during and following the eccentric exercise was decreased in the BCAA trial, suggesting a suppression of net muscle protein degradation. The plasma concentrations of interleukin (IL)-6 increased from 0.75+/-0.19 (pre-exercise) to 5.02+/-0.96 pg ml-1 (2 hrs post-exercise) in the control trial and in the BCAA supplementation trial from 1.07+/-0.41 to 4.15+/-1.21 pg ml-1. Eccentric exercise had no effect on the concentrations of neutrophils, lymphocytes, CD16+/CD56+, CD4+, CD8+, CD14+/CD38+, lymphocyte proliferative response or cytotoxic activities. BCAA supplementation reduced the concentration of CD14+/CD38+ cells. This study shows that the concentration of IL-6 in plasma is increased after prolonged eccentric exercise and suggests that the cytokine response is independent of the muscle proteolysis that occur during exercise.

Received 28 October 1996; accepted in final form 4 March 1997.
APS Manuscript Number E533-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 21 March 1997