Cytokine response to strenuous exercise in athletes and non-athletes - an adaptive response

Exercise and physical strenuous activity have been demonstrated to increase the serum TNF-alpha and IL-6. Regular physical training is expected to attenuate such a response. This study was undertaken to understand the impact of regular exercise training on IL-6 and TNF-alpha in athletes and non-athletes. Ten athletes, who have been on regular training for the past 6 months, and 10 age- and sex-matched subjects (non-athlete group) who had no practice of regular exercise, were recruited. Both were subjected to undergo the same frequency level of strenuous exercise. Blood samples were collected; one before strenuous exercise and the other after the exercise. Plasma cytokines, IL-6 and TNF-alpha, were estimated using Sandwich ELISA method. All participants in the study were male with the athletes' age being 18.00+/-1.3 years (mean +/- SD) and the non-athletes were aged 20.00+/-0.6 years (mean +/- SD). Majority of the athletes and non-athletes demonstrated a rise in IL-6 and a fall in TNF-alpha levels. Further, the athletes showed a lesser magnitude of change in the cytokine levels following a longer duration of exercise than non-athletes. Athletes appear to have an attenuated cytokine response. Regular physical training has been demonstrated to attenuate the immune response to exercise in either direction. (C) 2007 Elsevier Ltd. All rights reserved.