Immunoendocrine responses to physical stress

Background: The purpose of this study was to investigate the effect of single and repeated physical exercise on serum C- Reactive Protein, IL6 and Cortisol. Methods: Eight physical education students (mean age 21, s= 1.51 yrs, mean weight 74.25, s= 8.85 kg, mean height 178.2, s= 5.57 cm) volunteered to participate in the present study. In a periodized design, during 21 days subjects completed two trials and one control condition. Trial one, performing concurrent endurance (cycling for 45 min with 75 percent of maximal heart rate and resistance (6 exercise in 3 sets and 8 repetition with 80% IRM for 45 min) exercises in the afternoon, and trial two performing above exercises in the morning and afternoon. Blood Samples were taken before, immediately and 3 hours after exercises, while the subjects were overnight fast before first blood sampling (at least 12 h). Related variables of acute phase response (C-Reactive Protein, Interleukin 6 and Cortisol) were measured. Results: According to obtained data there were no significant changes in C-Reactive Protein, Interleukin 6 and cortisol after single and repeated bouts of selected exercises (P>0.05). Also, there were no significant differences in mentioned variables between single and repeated bouts in a day (P>0.05). Conclusion: An acute phase response does not seem to occur as a consequence of training protocols of this study.