Abstract
INTRODUCTION: Although reliable new evidence has identified several advantages of resistance training (ResEx) on cardiac performance, the role of this type of training in protecting the myocardium against ischemia-reperfusion (IR) injury is not clear. The aim of this study was to investigate the effect of resistance training on cardioprotection versus IR-induced injury. MATERIAL AND METHODS: 60-day-old male Wistar rats (n = 24), weighing 220-240 g, were divided into four groups: Resistance Training (ResEx), Isoproterenol (ISO), Resistance Training + Isoproterenol (ResEx + ISO), and control groups (n = 6 for each). Trained rats performed exercise in a squat-training apparatus (8-12 repetitions/set, eight sets/day, and 5 days/week for 8 weeks). After the last training session, all the rats were sacrificed with ketamine xylazine injection. The heart of rats was removed from the body and washed quickly with cold PBS, immediately put in liquid nitrogen, and stored at -70°C. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) activity was measured. RESULTS: Induction of ischemia decreased SOD and CAT activity but had no effect on the activity of GPX. Eight weeks of resistance training significantly increased activity of SOD and CAT compared to the ISO group. CONCLUSIONS: The results of the present research demonstrated that ischemia induced by isoproterenol injection during 8 weeks of resistance training did not lead to a decrease in SOD activity and prevented the reduction of CAT activity.