The Protective Effect of Interval and Continuous Exercise Training on Corticosterone, Weight Gain and Behavioral Despair in Rats Following a Period of Chronic Unpredictable Stress

Depression is one of the most common psychiatric disorders. Probably doing exercise training before coping with stressful situations can affect the symptoms of depression. Due to a variety of exercise training methods, the present study aimed at investigating the protective effect of continuous and high intensity interval training on corticosterone, weight gain and behavioral despair in rats following a period of chronic unpredictable stress. For this purpose, 27 adult male Wistar rats (9 weeks, 200±20 g) were divided into continuous training, interval training, and sedentary group. The exercise training was progressive and included running on treadmill for five days per week within six weeks. Interval training was consisted of two to six two-minute periods with speed of 38 to 42 m/min and continuous training was 22 to 42 minutes with speed of 23 to 27 m/min. After the training period, the rats were exposed to stress for three weeks. Finally, forced swim test was performed and the plasma corticosterone level was measured. The weight of rats was measured every week. The results indicated that the continuous exercise training group had lower corticosterone and less immobility in forced swim than the control group. The rats of all three groups had significantly less weight gain during the stress period than the training period. In general, the continuous exercise had an acceptable protective effect on corticosterone secretion and despair. However, none of the exercise trainings could affect the improvement of weight gain.