Objective: The purpose of this study was to examine the effects of 8 weeks of resistance training on plasma growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels in inactive adolescents.
Methodology: A quasi-experimental design was employed with 24 inactive adolescents who were randomly assigned to either an experimental group (n=12) or a control group (n=12). The experimental group participated in an 8-week resistance training program consisting of three 60-minute sessions per week. The training protocol included exercises targeting major muscle groups such as squats, deadlifts, bench presses, and shoulder presses, with 3 sets of 8-12 repetitions at 70-75% of one-repetition maximum (1RM) for the first 4 weeks, progressing to 80-85% of 1RM during the final 4 weeks.
Results: The results showed significant increases in plasma GH and IGF-1 levels in the experimental group after the 8-week resistance training program (GH: p = 0.001; IGF-1: p = 0.009). In contrast, the control group showed no significant changes in either GH or IGF-1 levels (GH: p = 0.250; IGF-1: p = 0.312). These findings suggest that resistance training effectively enhances hormonal responses in inactive adolescents, particularly with regard to GH and IGF-1 secretion.
Conclusion: The study concluded that 8 weeks of resistance training significantly increased GH and IGF-1 levels in inactive adolescents. These findings emphasize the role of resistance training as an effective intervention to improve hormonal health and support physical development in this population.