Shahid Beheshti University Journal of Sport and Exercise Physiology 2676-3710 15 2 2022 04 21 The effect of eight weeks of high-intensity interval training vs. continuous training on serum Irisin levels and expression of skeletal muscle PGC-1α gene in male rats with metabolic syndrome The effect of eight weeks of high-intensity interval training vs. continuous training on serum Irisin levels and expression of skeletal muscle PGC-1α gene in male rats with metabolic syndrome 95 103 102276 10.52547/joeppa.15.2.95 FA Zohreh Borhani Kakhki Department of Physical Education, Farhangian University, Tehran, Iran Sheila Naibifar Department of Sports Science, Faculty of Educational Sciences and Psychology, Sistan and Baluchestan University, Zahedan, Iran Hossein Nakhaei Department of Physical Education, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran Elham Ghasemi Department of Sport Sciences, Faculty of Literature and Humanities, University of Zabol, Zabol, Sistan & Baluchestan, Iran Journal Article 2021 08 22 <strong>Purpose</strong>: An imbalance in the production of PGC-1α and myokines impairs the energy expenditure, increases adipocyte and develops metabolic pathologies, but physical exercise is able to regulate the secretion of myokines through PGC-1α. The aim of this study was to evaluate the effect of eight weeks of high-intensity interval training vs. continuous training on serum Irisin levels and expression of skeletal muscle PGC-1α gene in male rats with metabolic syndrome<br /><strong>Methods</strong>: 32 Wistar male rats, with six weeks’ age and weight 150-180 gr, randomly divided into two groups including standard diet (n=8) and high fat diet (n=24). They were then placed on a pre-exercise diet for 12 weeks. 24 rats from high fat diet group were divided randomly into two groups including metabolic syndrome control (Ctr+MS), continuous running (CT-MS) and Interval running (IT-MS). Continuous and interval training for eight weeks were performed on 65-75 and 80-100% of the maximum speed on the treadmill for mice, respectively. The ELISA method for measuring serum Irisin levels and real-time PCR method for expression of PGC-1α gene were used. The data were analyzed by one-way analysis of variance (ANOVA), Tukey's post-hoc test and Pearson correlation at P < 0.05 level.<br /><strong>Results</strong>: After eight weeks of interval and continuous training, PGC-1α expression (P = 0.01 and P= 0.001) and serum levels of Irisin (P = 0.01 and P= 0.001) increased compared to the metabolic syndrome control group, and this increase was more evident in the interval group than the continuous group (P = 0.001). Muscle expression of PGC-1α was also positively correlated with serum Irisin levels in mice (P = 0.001, r = 0.8).<br /><strong>Conclusion</strong>: It seems that the use of interval exercises can increase the expression of PGC-1α gene and Irisin as much as continuous exercise and possibly improve metabolic disorders in people with metabolic syndrome. <strong>Purpose</strong>: An imbalance in the production of PGC-1α and myokines impairs the energy expenditure, increases adipocyte and develops metabolic pathologies, but physical exercise is able to regulate the secretion of myokines through PGC-1α. The aim of this study was to evaluate the effect of eight weeks of high-intensity interval training vs. continuous training on serum Irisin levels and expression of skeletal muscle PGC-1α gene in male rats with metabolic syndrome<br /><strong>Methods</strong>: 32 Wistar male rats, with six weeks’ age and weight 150-180 gr, randomly divided into two groups including standard diet (n=8) and high fat diet (n=24). They were then placed on a pre-exercise diet for 12 weeks. 24 rats from high fat diet group were divided randomly into two groups including metabolic syndrome control (Ctr+MS), continuous running (CT-MS) and Interval running (IT-MS). Continuous and interval training for eight weeks were performed on 65-75 and 80-100% of the maximum speed on the treadmill for mice, respectively. The ELISA method for measuring serum Irisin levels and real-time PCR method for expression of PGC-1α gene were used. The data were analyzed by one-way analysis of variance (ANOVA), Tukey's post-hoc test and Pearson correlation at P < 0.05 level.<br /><strong>Results</strong>: After eight weeks of interval and continuous training, PGC-1α expression (P = 0.01 and P= 0.001) and serum levels of Irisin (P = 0.01 and P= 0.001) increased compared to the metabolic syndrome control group, and this increase was more evident in the interval group than the continuous group (P = 0.001). Muscle expression of PGC-1α was also positively correlated with serum Irisin levels in mice (P = 0.001, r = 0.8).<br /><strong>Conclusion</strong>: It seems that the use of interval exercises can increase the expression of PGC-1α gene and Irisin as much as continuous exercise and possibly improve metabolic disorders in people with metabolic syndrome. https://joeppa.sbu.ac.ir/article_102276_e4c5039108c3d12cb6877dd0a154ce3d.pdf