Acute Interval Walking with and without Vascular Occlusion has a Different Effect on 4EBP1 Phosphorylation and Stimulation of the mTOR Signaling Pathway in the Skeletal Muscle of Inactive Men

Abstract

Background: Low-intensity aerobic exercise can cause muscle hypertrophy if accompanied with vascular occlusion. Aims: The purpose of the study was to compare of effect of acute interval walking with and without vascular occlusion on phosphorylation of 4EBP1 and stimulate the mTOR signaling pathway of skeletal muscle in inactive men.

Materials and Methods: Five healthy inactive men participated in this study on 2 separate days 2 weeks apart. The first session of the research protocol consisted of acute interval walking with vascular occlusion and the second session consisted of acute interval walking without vascular occlusion. Session one was including vascular occlusion by 5 intervals 2-min walking at 60% Maximum heart rate (MHR) and 1 min at rest. The second session was similar to the first but without vascular occlusion. All samples were collected 30 minutes before the start and 3 hours after training. Concentration of 4EBP1 skeletal muscle were evaluated by Western blotting. Dependent t-test and Independent t-test was used to analyze the data after subtracting the post-test score from the pre-test.

Results: There was a significant difference between pre and post-test of 4EBP1 in the group with vascular occlusion and the mTOR signaling pathway was stimulated (P=0.001). There was no significant difference in the second group (P=0.064). Also, significant differences were reported between the two training methods for 4EBP1 phosphorylation and stimulation of the mTOR signaling pathway (P = 0.01), (P≥0.05).

Conclusion: If acute interval walking is associated with vascular occlusion, it can increase 4EBP1 phosphorylation and stimulate the mTOR signaling pathway, leading to muscle hypertrophy.