The effect of 12 weeks of resistance training on the serum levels of FGF6 and MyoD and its relationship with muscle strength in middle-aged men and women

It seems that during resistance exercises, the release of some growth factors has different effects on the activation of satellite cells (SCs) and myogenic regulatory factors as well as the development of strength and muscle mass. Therefore, this study aimed to investigate the effect of 12 weeks of resistance training on the serum levels of FGF6 and MyoD and its relationship with muscle strength in middle-aged men and women. In this semi-experimental study, 40 randomly selected middle-aged men and women from Arak city (age: 38.27±6.03 years, weight: 77.12±11.28 kg, height: 174.05±7.24 cm) were chosen. They were placed in two experimental groups (n: 30) and control (n: 10). The training program included 12 weeks of resistance training in 3 sessions per week with an intensity of 65-80% of one repetition maximum (1RM). Then, 48 hours before and after the intervention, the serum concentration of FGF-6 and MyoD was measured by the ELISA method, and after checking the normality of the data, t-test and independent t-test were used to check intra-group and inter-group changes, respectively. Pearson's correlation coefficient was used to check the relationship between variables at a significance level of p<0.05. Resistance training increased mean maximal strength (P=0.008), serum FGF6 concentration (P=0.002), serum MyoD concentration (P=0.001) and also decreased fat percentage (P=0.021) of the subjects. In addition, there was a positive and significant correlation between the mean maximum strength (1RM) and the serum concentration of FGF6 (r=0.624 and P=0.001) and MYoD (r=0.434 and P=0.001) of the training group. Considering the importance of resistance training in the elderly and the relationship between the plasma levels of FGF6 and MYoD with strength development, it is suggested that sports experts pay special attention to the necessity of resistance training in the design of various sports exercises.