Comparison of the effects of endurance, resistance and concurrent training on insulin resistance and adiponectin-leptin ratio in diabetic rat

Background: The obesity-related hormones leptin and adiponectin are independently and oppositely associated with insulin resistance. Objective: The aim of the present study was to investigate the effect of endurance, resistance and concurrent training on insulin resistance and adiponectin-leptin ratio in diabetic rats. Methods: Ten out of 50 male Wistar rats were separated as healthy subjects. Then diabetes was induced in the remaining rats by the injection of streptozotocin. Diabetic rats divided into 4 groups: Control, resistance training (5 sessions/week, 4 reps/3 sets), endurance training (5 sets per week of treadmill running) and concurrent training. The resistance training protocol consisted of ten weeks climbing up the ladder, while endurance training performed on treadmill for ten weeks. Concurrent training group completed a combination of both resistances and endurance treadmill training. Blood samples were taken to assess leptin, adiponectin and insulin resistance. Findings: Endurance, resistance and concurrent training significantly decreased insulin resistance and glucose (P<0.05), although concurrent training lead to greater decreases in insulin resistance (P<0.05). There were no significant differences in leptin levels in any of the groups (P>0.05). On the one hand, adiponctin level and adiponctin-leptin ratio significantly increased in all of training groups (P<0.05). Conclusion: Exercise training, as defined in this study, leads to improvements in adiponectin-leptin ratio and concurrent training has more impact on insulin resistance index in diabetic rats.