Effects of transcutaneous electric acupoint stimulation on plasma SOD and MDA in rats with sports fatigue

OBJECTIVE To observe the effect of transcutaneous electric acupoint stimulation (TEAS) on plasma superoxide dismutase (SOD) and malondialdehyde (MDA) in rats with sports fatigue so as to explore its mechanisms in resisting exercise-induced fatigue. METHODS Twenty-seven male adult SD rats were randomly divided into control group (n 9), model group (n=9) and TEAS group (n=9). Sports fatigue model was established by using treadmill method, i.e. forcing the rat to run 10 min at a speed of 10 m/min, 15 m/min, 20 m/min, 24 m/min and 28 m/min, once daily for 6 days. TEAS (continuous waves, 2 Hz, 5 mA) was applied to unilateral Zusanli (ST 36) for 30 min, once per day for 7 days. The exhausted exercise time from starting running to exhaustion was recorded on the 7th day and the lactate levels, SOD activity and MDA contents in plasma were measured by lactate oxidase method, xanthine oxidase method and thiobarbituric acid method respectively. RESULTS The duration of exhausted exercise in model group and TEAS group were (56.00 +/- 12.27) min and (70.88 +/- 13.74) min respectively, displaying significant increase in exercise tolerance after TEAS (P 0.05). SOD/MDA of model group was significantly lower than those of control group and TEAS group (P<0.05, 0.01). CONCLUSION TEAS at Zusanli(ST 36) can effectively postpone exercise-induced fatigue by reducing accumulation of blood lactate, improving anti-oxidative ability and relieving lipid peroxidation in the rat.