Effect of Resistance Training along with Electrical Muscle Stimulation on Serum Levels of Some of the Molecular Markers of Muscle Hypertrophy in Male Athletes after Anterior Cruciate Ligament Surgery

Introduction: To the best of our knowledge, there is no study to examine the effect of a combination of resistance training and electrical muscle stimulation (EMS) on muscle hypertrophy factors in injured athletes. This study aimed to evaluate the effect of EMS on serum levels of some molecular markers of muscle hypertrophy in male athletes after anterior cruciate ligament surgery. Materials and Methods: For the study, 20 volunteer men were randomly divided into 2 groups (10 people in each group), the EMS-resistance training and control groups. Subjects in both groups performed 2-4 sets of lower body resistance training movements with an intensity of 30-70% of ten repetitions maximum for 12 weeks. The subjects in the EMS-resistance group performed exercise movements combined with electrical stimulation at 35-70 Hz. Blood samples were collected from all subjects before and 48 hours after the last training session and used to measure the levels of sirtuin-1 (SIRT1), visfatin, and nitric oxide (NO). Data were analyzed using analysis of covariance and paired sample t-test. Results: The results showed that 12 weeks of EMS training significantly increased serum levels of SIRT1 (P < 0.001), visfatin (P = 0.02), and NO (P = 0.01) in the post-test compared to the pre-test. Significant differences were observed between the EMS and control groups in SIRT1 (P < 0.001) and NO (P = 0.021) levels. In addition, there was no significant difference between the groups in serum visfatin level (P = 0.098). Conclusion: The findings suggest that EMS in combination with resistance training could be a good alternative to traditional resistance training to stimulate factors related to muscle protein synthesis after anterior cruciate ligament reconstruction.