Effects of Eight-Week Strength Training on Basal Hormone Levels, Oxidative Stress Markers and IL-6 Levels in Adolescent Athletes

Abstract

Purpose This study investigated how strength training affects adolescent athletes' hormonal, cytokine, and oxidative stress markers. Methods The participants were split into two groups: Strength training (ST) (n=10) and control (C) (n=10). The strength training group participated in 8-week handball and strength training. The Control group followed their weekly handball training routine. The ST group participated in traditional strength training 3 days a week in addition to handball training for 8 weeks. We quantified hormone, oxidative stress markers and IL-6 in the subject’s blood samples. Result Interestingly Insulin-like growth factor-1 concentration declined in the C group (p<0.05), while the ST serum concentrations did not change statistically (p>0.05). Insulin-like growth factor binding protein-3 (IGFBP3) and sex hormone binding globulin (SHBG) concentration of the ST decreased but did not in C. Serum-free testosterone (FT) levels increased in both groups, while total testosterone levels did not change. While total antioxidant status (TAS) and antioxidants stress index (ASI) did not change, total oxidant status (TOS) and oxidative stress index (OSI) reduced both groups (p<0.05). Serum interleukin-6 (IL-6) levels did not alter ST and C groups. Conclusion While strength training did not affect serum concentrations of testosterone, GH, IGF-1, Cortisol, IL-6, and total antioxidant status, it caused a decrease in SHBG and IGFBP3. Serum FT levels increased in ST and C groups. Also, serum TOS levels declined ST and C; it is unclear whether strength training affects the increase in free testosterone or the decrease in TOS levels.