(1.College of Physical Education,South China Nomal University,Guangzhou 510631,China;2.Department of Sports Human Science,Guangzhou Institute of Physical Education,Guangzhou 510500,China) Abstract: In order to probe into the effects of hypoxia and exercising on the super-oxidizing and oxidation resisting capability of the lipid of mitochondria of skeletal muscles (MSM) of fat and normal rats, the authors randomly di-vided 100 healthy male rats into a normal control group of 40 rats and a group of 60 rats for fat model establish-ment, selected 40 rats from the fat model successfully established Sprague Dauley rats and randomly divided them into a normoxic resting group, a normoxic exercising group, a hypoxic resting group and a hypoxic exercising group (each group contains 10 rats), divided the control group into a normal normoxic resting group, a normal normoxic exercising group, a normal hypoxic resting group and a normal hypoxic exercising group (each group contains 10 rats), sampled the homogenate of skeletal muscles (gastrocnemius and quadriceps femoris) of the posterior limbs of the rats to extract mitochondria in about 24 h after the last hypoxic exercising was performed in week 4 (all the rats were starved at the night before sampling), and tested the MDA content and SOD activity of MSM of rats in the fat model established groups and normal groups. The authors revealed the following findings:(1) as for MSM of rats in the normal groups, their SOD activity is significantly higher than that of rats in the fat model established groups (P<0.01), while their MDA content is lower than that of rats in the fat model established groups, but which is not significant statistically; as for MSM of rats in the aerobic exercising groups, their SOD activity is higher than that of rats in the resting groups, while their MDA content is lower than that of rats in the resting groups, but those are not significant statistically; (2) as for MSM of rats in the hypoxic resting groups, their SOD activity is significantly higher than that of rats in the normoxic resting groups (P<0.01), while their MDA content is lower than that of rats in the normoxic resting groups, but which is not significant statistically; (3) as for MSM of rats in the hypoxic exer-cising groups, their SOD activity is significantly higher than that of rats in the normoxic exercising groups (P<0.05), while their MDA content is lower than that of rats in the normoxic exercising groups, but which is not significant statistically. These research findings revealed the followings: the free radical resisting capability of the body of fat rats is inferior to that of normal rats, yet exercising and hypoxic stimulation can improve such a condi-tion; 4 weeks of aerobic exercising and hypoxic stimulation had boosted the oxidation resisting capability of the body, and enhanced the free radical removing capability; the combination of exercising and hypoxic stimulation can make the oxidation resisting capability and free radical removing capability of the body more powerful. Key words: exercise biochemistry;fat rat;intermittent hypoxia;aerobic exercise;free radical;mitochondrion |