Journal
APPLIED PHYSIOLOGY NUTRITION AND METABOLISM
Volume 31, Issue 3, Pages 226-234Publisher
CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS
DOI: 10.1139/H05-029
Keywords
CD69; DHEA; lymphocytes; exercise
Categories
Ask authors/readers for more resources
The effects of exercise training on lymphocyte responses, as well as changes in circulating endocrine parameters at rest, were investigated. Seven male cyclists participated in a 4 week high-intensity (HI) cycling training intervention. Training improved performance significantly (peak power output (PPO): 1.4%, p < 0.05; 5 km time trial: 3.8%, p < 0.01; 40 km time trial: 0.4%, p < 0.05). Resting hormone concentrations (testosterone, sex hormone binding globulin (SHBG), cortisol, corticosteroid-binding globulin (CBG), and dehydroepiandrosterone-sulphate (DHEA-S)) were unchanged, with the exception of a 20% decrease in testosterone post-HI training (p < 0.067). Subjects' CD3(+) cell counts decreased by 15% (p < 0.05), owing to significantly decreased CD4(+) cell counts and slightly lower CD8(+) and natural killer (NK) cell counts. Spontaneous in vitro CD69 expression increased in CD4(+) cells (mean +/- SD, pre: 12 +/- 6 cells.mu L-1; post: 35 +/- 37 cells.mu L-1; p < 0.05), but not in CD8(+) cells (pre: 20 +/- 29 cells.mu L-1; post: 33 +/- 16 cells.mu L-1). Mitogen-induced CD69 expression decreased in both CD4(+)cells-gL-1). Mitogen-induced CD69 expression decreased in both CD4+ (pre: 1570 1258 cells-pL-1; post: 596 +/- 597 (pre: 1570 +/- 1258 cells-pL-1; post: 596 +/- 597 cells.mu L-1; p < 0.05) and CD8(+) lymphocytes (pre: 676 +/- 434 cells.mu L-1; post: 412 +/- 235 cells.mu L-1; p < 0.05). Testosterone correlated positively with several immune parameters at baseline, whereas cortisol correlated negatively with parameters of the innate immune system post-HI training. We conclude that the stress of unaccustomed exercise is evident in resting lymphocytes, but not in resting endocrine parameters. However, correlations between testosterone and cortisol and immune parameters suggest that these 2 hormones play a role in modulating immune status. Our results indicate the importance of assessing both spontaneous and mitogen-induced aspects of immune-cell activation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available