The Effect of Endurance, Strength and Concurrent Training on Plasma Level of IL-6 and Cortisol in Untrained Men

This study is to investigate the effects of 10 weeks of endurance (E), strength (S) and concurrent (combined E and S) training on plasma level of IL-6 and cortisol in untrained men. In this semi-experimental study, 38 healthy volunteer males (age 24.89±1.21 yrs, height 175.87±6.52 cm, weight 71.98±9.33 kg) were randomly assigned to endurance (N=10), strength (N=9), concurrent (N=10), and control group (N=9). Treatment was conducted three times per week. After 10 weeks, the maximal bench press and squat strength of strength and concurrent groups were improved significantly (P≤0.05). Similar increment was observed in VO2max in endurance and concurrent groups (P≤0.05). Endurance training didn’t have any significant effect on IL-6 (p=0.107), and cortisol (p=0.38) levels. Strengths training also didnt affect on IL-6 (p=0.63), but resulted in a significant increment in plasma level of cortisol (p=0.001). There wasn’t any significant effect of concurrent training on IL-6 (p=0.162) and cortisol levels (p=0.38). However, only the difference (D) of changes in IL-6 in the concurrent group was significantly lower than control groups (p= 0.016, 0.710±1.475 vs 0.855±1.31). In conclusion, our results showed that adding the strength training to endurance training, not only, does not compromise the immune function in untrained men, but also can efficiently improve its function.