Effects of acute exercise on serum interleukin-17 concentrations in hot and neutral environments in trained males

Abstract

The purpose of this study was to determine the effects of acute exercise on IL-17 concentrations in hot and neutral environments in trained males. Ten trained, non-heat acclimated males performed two 1h run on treadmill at 60% VO2max in neutral (22±1°C, 50±5RH) and hot (35±1°C, 50±5) temperature conditions. Samples of the venous blood were taken (Pre, post, 2h post) for determination of serum IL-17, cortisol concentrations and numbers of leukocytes and neutrophils. In addition, body temperature, RPE and PVC during exercise were measured. The collected data were analyzed using the Repeated-Measures analyses of variance and Bonferroni post hoc and Paird T tests (p<0.05). The concentration of cortisol and total number of leukocytes increased significantly after exercise, in both conditions (p<0.0001) and were significantly higher in hot than neutral (p=0.016, p=0.002). During the rest period (2h post) the number of neutrophils increased significantly in hot environment (p=0.018). The concentrations of IL-17 increased significantly only after exercise in hot (p<0.0001) and were significantly higher during hot than neutral (p=0.002). The results suggest that exercise in hot environment cause increase in body temperature, perceived exertion and cardiac-vascular changes which are sufficient to elicit immune, hormonal and inflammatory responses. The present results confirm the additive effect of heat stress on the IL-17 response during exercise.