Mania Roozbayani - Coach of Exercise Physiology, Department of Exercise Physiology, Boroujerd, Islamic Azad University, Boroujerd, Iran.
Maghsoud Peeri - Professor of Exercise Physiology, Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Hamid Agha-Alinejad - Associate Professor of Exercise Physiology, Faculty of Humanities, Tarbiat Modares University, Tehran, Iran.
Mohammad Ali Azarbayjani - Professor of Exercise Physiology, Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.

Objective: High intensity interval training (HIIT) and continues aerobic training have cardio-protective effects in diabetic rats. The aim of this study was to compare the effect of HIIT and continues aerobic training (CAT) on MIR۲۹A and collagen I gene expression in heart of diabetic male rats. Materials and Methods: In this randomized controlled clinical trial, ۱۸ male diabetic rats were studied. They were divided into ۳ groups as HIIT, CAT and control group. Exercise protocol was performed ۵ days/week for ۵ weeks. The MIR۲۹A and collagen I synthesis were compared between the groups. Results: Findings showed MIR۲۹A expression is statistically higher in HIIT and CAT group than control group (P-value<۰.۰۰۱) and (P-value:۰.۰۵۳). Also MIR۲۹A expression is significantly higher in HIIT group compared to CAT group (P-value:۰.۰۳۴). Collagen I expression was significantly lower in HIIT and CAT group compared to control group (P-value<۰.۰۰۱) and (P-value:۰.۰۰۱). Collagen I expression was lower in HIIT group compared to CAT group (P-value:۰.۰۲۷). Discussion: The results of this study demonstrated that, HIIT increases MIR۲۹A expression which is along with reduction in collagen I synthesis in cardiac muscles increases the risk of myocardial fibrosis in diabetic rats.

High intensity interval training, Continues aerobic training, Diabetic rats, MIR۲۹A, Collagen I