Exercise Physiology
Masoud Asgharpour-arshad; HASSAN POURRAZI; Rasoul Bakhshi
Abstract
Aim: The aim of this study was to determine the effect of 12-week high-intensity interval training on heart mass and expression of beta-catenin and glycogen synthase kinase-3-beta genes in myocardial tissue of male rats.Method: Thirty male Wistar rats were randomized into three groups, including sham ...
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Aim: The aim of this study was to determine the effect of 12-week high-intensity interval training on heart mass and expression of beta-catenin and glycogen synthase kinase-3-beta genes in myocardial tissue of male rats.Method: Thirty male Wistar rats were randomized into three groups, including sham (n = 10), control (n = 10), and HIIT (n = 10). The experimental group underwent HIIT consisting of 2 - 8 repetitions of 4-min high-intensity intervals (85% - 90% peak speed) interspersed with low-intensity intervals (45% - 50% peak speed), performed five times/week over 12 weeks. Forty-eight hours after the last training session, animals’ hearts were removed. The gene expressions of beta-catenin and glycogen synthase kinase-3-beta were analyzed by the RT-PCR method. The independent t-test was used for statistical analysis (P < 0.05).Results: The results showed that the body weight was significantly lower in HIIT group (P = 0.029) and heart/body weight ratio were significantly higher in the intervention group than in the control group (P = 0.001). Also, beta-catenin gene expression were significantly higher in trained rats than the control group (P = 0.002). Regarding GSK3-β genes expression, although mean levels were lower in the trained group than the control, the differences were statistically insignificant (P = 0.71).Conclusions: HIIT training, along with considerable reduction of body weight, increase the ratio of heart to body weight and cardiac hypertrophy. Also, these exercise training trigger cardiac hypertrophic signals by stimulating the Wnt signaling pathway and significantly increasing beta-catenin gene expression.
Mohammad Mahdi Bagherpour Tabalvandani; Mohammad Reza Fadaei; Alireza Elmieh
Abstract
The aim of this study was to evaluate the effect of aerobic resistance training on the growth of muscle fibers, testosterone and androgen receptors in male rats of different age groups. 30 male Wistar rats, child (n=10), young (n=10) and elderly (n=10), were divided into two groups of training and control ...
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The aim of this study was to evaluate the effect of aerobic resistance training on the growth of muscle fibers, testosterone and androgen receptors in male rats of different age groups. 30 male Wistar rats, child (n=10), young (n=10) and elderly (n=10), were divided into two groups of training and control Exercise were performed intermittently, one day for resistance and one day for aerobic for 6 weeks. 48 hours after the last training session, anesthesia, blood sampling and then were killed and then gastrocnemius and soleus muscles were extracted. Blood serum was also isolated and then blood testosterone was measured by ELISA, muscle growth was measured by light microscopy and gene expression of androgen receptors was measured using Real-time pcr. The results showed that the cross- sectional of muscle fiber in all three training groups of ages contains: child (p=0.001), young (p=0.003) and elderly (p=0.001) were more than control groups. There were no significant difference in serum testosterone between training and control groups of child (p=0.6), while serum testosterone in young (p=0.008) and elderly (p=0.001) training groups were more than controls. Also there were no significant difference in expression of androgen receptors between training and control groups of child (p=0.3), young (p=0.3) and elderly (p=0.8). The results showed that resistance-aerobic exercise can cause muscle hypertrophy at different ages by increasing testosterone concentration. Resistance-aerobic training can accelerate the growth process and also prevent muscle atrophy in old age.
