| An effective method to treat and prevent a multitude of chronic diseases is to reduce chronic inflammation through regular exercise. The anti-inflammatory effect of exercise is predominantly due to the production of Interleukin-6 (IL-6) from the active skeletal musculature. Heat alone produces an inflammatory effect. However, the effect of IL-6 when exercising in different environmental conditions is currently unknown. The purpose of this study was to determine the effects of exercise in hot, room temperature, and cold environments on plasma IL-6. Eleven recreationally trained males (age = 25 +/- 4 y, height = 178 +/- 5 cm, weight = 79.4 +/- 13.5 kg, 14.7 +/- 3.6 % body fat, VO2 peak = 4.29 +/- 0.86 L ˙ min-1, Wmax 277 +/- 41 W) performed a 1 h cycling bout in hot (H), cold (C), and room temperature (RT) environments (33 °C, 7 °C, 20 °C, respectively) followed by 3 h of supine recovery at room temperature. Expired gases were measured every 15 minutes during exercise and once every hour during recovery. Heart rate (HR) was continuously measured throughout trial. Blood samples were obtained from the antecubital vein pre-exercise, immediately post-exercise, and 3 h post-exercise. Blood samples were analyzed for plasma concentrations of IL-6 using a commercial ELISA kit. Plasma IL-6 concentrations were higher immediately post-exercise (14.8 +/- 1.6 pg˙ ml-1, p = 0.008) and 3 h post-exercise (14.8 +/- 0.9 pg˙ ml-1, p = 0.018) compared to pre-exercise (11.4 +/- 2.4 pg˙ ml-1 ) regardless of trial. There were no differences in plasma IL-6 concentrations (p = 0.207) between H, C, and RT. VO2 and HR were higher and RER was lower in the hot compared to other conditions (p < 0.05) This data indicates that the temperature in which exercise occurs does not affect acute plasma IL-6 response despite differences in metabolic state. |
