The Effect of Eight Weeks of Moderate and High Intensity Resistance Training on Muscular miR-1, miR-206 Expression and Serum IGF- I in Wistar Older Rats

One of the most important and prevalent consequences in elderly people is age-related muscular atrophy or Sarcopenia. Sarcopenia is associated with a significant reduction in muscle strength and mass. The purpose of this study was to investigate the effect of moderate and high intensity resistance training on miR-1, miR-206 expression and serum IGF-1 in elderly rats. 30 male Wistar rats (23 months old) were randomly divided into two experiment and one control group including moderate intensity resistance training (n = 9), high intensity resistance training (n = 8) and the control group (n =8. Resistance training included 8 weeks of climbing a ladder with high intensity (80% MVCC) and moderate intensity (60% of MVCC) and 5 days a week. After completing training, miR-1, miR-206 expression was measured using the by RT-PCR method in Soleus and FHL muscle and IGF-I in serum. The statistical analysis was performed using One Way ANOVA test with significance level of  (P <0.05). The results showed that in both resistance training group, miR-1 and miR-206 expression were significantly lower than those in control group and IGF-1 concentrations was significantly higher in both high and moderate resistance groups than control group (P <0.05). High intensity resistance training was more effective for both miR-1 and miR-206 in FHL muscle and serumIGF-1. It seems that resistance training with moderate and high intensity can change the resting levels microRNAs related to muscular atrophy (miR-1, miR-206) and its target gene (IGF-1) in older rats and lead to the prevention of sarcopenia in older peoples.