Effect of Eight Weeks of Resistance Training on Some Signaling Factors Affecting on the Satellite Cells in Wistar Rats

The purpose of the present study was to determine the effect of eight weeks of resistance training on some signaling factors including myostatin، transforming growth factor-β (TGF-β) and fibroblast growth factor-2 (FGF-2) which affect satellite cells in Wistar rats. 20 adult male Wistar rats (150-250 g) provided by the Isfahan University of Medical Sciences، were randomly divided into 2 groups [control group n = 10 (C); resistance training group n = 10 (R)]. Resistance training was conducted for 8 weeks (5 sessions/week) on a special 1-meter high ladder (divided by 26 stairs) with the loading of 30% of body weight (suspended from the tail) in the first week and increased to 200% of body weight in the last week. Training included 3 sets of 4 reps with 3 minutes rest between sets. T-test analysis of the changes of all three myostatin، TGF-β and FGF-2 factors showed that the mean plasma level of myostatin decreased [71. 8 ± 19. 6 mg/dl (R) ver. 105. 8 ± 17. 4 mg/dl (C); P = 0. 001]، but the level of FGF-2 increased significantly [102. 4 ± 11. 1 mg/dl (R) ver. 86. 5 ± 12. 6 mg/dl (C); P = 0. 048] in resistance training group. In contrast، the serum level of TGF-β was not statistically different between the two groups [153. 4 ± 54. 0 mg/dl (R); 160. 6 ± 32. 8 mg/dl (C); P = 0. 725]. This study showed that resistance training reduces serum levels of myostatin and increases serum levels of FGF-2 that both are factors affecting satellite cells that play a role in increasing muscle strength. Although not being significant between groups، the serum level of TGF-β was reduced in the experimental group.