Comparing the effect of 8 weeks of continuous aerobic and high intensity interval training on soleus muscle gene expression of mTORC1, eEF2K eEF2 in male Wistar rats

Document Type : Original Article

Authors

1 Department of Exercise Physiology, Faculty of Sport and Exercise Sciences, University of Tehran, Tehran, Iran.

2 Department of Biological Science in Sport and Health, University of Shahid Beheshti, Tehran, Iran.

Abstract

Abstract
Background and purpose: The mechanism of MPS is controlled by mTORC1 pathway and specific downstream pathways, including eEF2, which maximizes fiber gain in skeletal muscle. The purpose of this study was to compare the effect of 8 weeks of continuous aerobic and high intensity interval training (HIIT) on soleus muscle gene expression of mTORC1, eEF2K eEF2 in male Wistar rats.
Material and methods: For this purpose, twenty-four male Wistar rats (8 weeks old; 280-300 g) were randomly divided into three groups: high intensity interval training (n=8), continuous aerobic training (n=8) and control (n=8). The exercise protocol consisted of an 8-week continuous aerobic and HIIT program (three times per week) that began with a 15-degree incline. The HIIT protocol included eight-minutes of high intensity repetitions at an intensity of 85-95 % vo2max followed by active recovery at an intensity of 50-60 % vo2max. The intensity of the exercise increased from two full repetitions in the first week to five repetitions. In the continuous aerobic group, the rats ran at an intensity of 65-75% of vo2max and the training time increased from 30 minutes in the first week to 60 minutes in the fourth to last week. For warm-up and cool-down, the subjects ran at 40-50% of VO2max for 10 minutes at the beginning and end of each training session. 48 hours after the last training session, the soleus muscle of the rats was extracted and the factors were evaluated by real-time PCR. Data were analyzed by one-way ANOVA with post hoc LSD at a significant level of P≤0.05.
Results: The results of the study showed that continuous aerobic training on the treadmill caused a significant increase in the weight ratio of muscle mass to body weight (p = 0.01) and expression of eEF2K gene (p = 0.002). Despite the increase in mTORC1 in the training group, changes in mTORC1 (p ≥ 0.05) and eEF2 (p ≥ 0.05) were not statistically significant.
Conclusion: Our results showed that 8 weeks of continuous aerobic training and high-intensity interval training on a 15-degree incline treadmill increased mTORC1 gene expression and the ratio of soleus muscle weight to body weight. Given the increased expression of eEF2K and no change in eEF2 in both exercise groups, it appears that the elongation pathway does not play a role in the potential hypertrophy caused by either type of exercise.
Keywords: Continuous aerobic training, high intensity interval training, eEF2, eEF2K, mTORC1

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Main Subjects



Articles in Press, Accepted Manuscript
Available Online from 19 May 2025
  • Receive Date: 20 January 2025
  • Revise Date: 26 April 2025
  • Accept Date: 19 May 2025
  • First Publish Date: 19 May 2025
  • Publish Date: 19 May 2025