The Effect of Eight Weeks Circuit Resistance Training on the Levels of Interleukin-15, IGF-I and IGFBP-3 in Overweight Males

Interleukin-15 (IL-15) is an important cytokine that secreted from skeletal muscles in response to exercise and has a different effect on various tissue such as muscular tissue. Present study conducted aimed to investigate the effect of eight weeks of circuit resistance training on serum levels of IL-15 in young overweight males. 20 overweight young males (BMI: 26.32±0.98 kg.m2) randomly divided into two control and circuit resistance training groups (n=10). Circuit resistance training program performed for eight weeks and three session per week. Each training session consisted of nine exercise that performed with 50 to 60 percent of 1RM. Over this time, the subjects in control group continue their routine daily program. After 48 hours from the last training session, post-test blood samples taken up to 7 ml from brachial vein, as in pre-test, in order to measurement the levels of desired variables including IL-15, IGF-I and IGFBP-3. Present study findings indicated that changes in the levels of IL-15, IGF-I and IGFBP-3 were not statistically significant between the control and circuit resistance training groups (p>0.05). However, percent body fat in trained group indicated significant decrease compared to control group (p=0.003). According to present study findings, it seems that circuit resistance training positive effects over eight weeks in overweight young males is mediated by other pathways beside the changes in levels of studied variables including IL-15.