If the load exercise exceeds a certain degree, it will lead to sports injury. The main reason for this phenomenon is that the human body produces a lot of free radicals after sports training. Free radicals can attack human cells and cause lipid peroxidation to damage cell membrane. The human body can improve the antioxidant capacity of the body by supplementing some trace elements. Selenium, iodine, zinc, iron, and calcium are all trace elements that contribute to antioxidants in the body. Nanoselenium is of great interest among many immune modulators because of its high antioxidant properties and remarkable immune protective function. In this paper, grey rabbits were used as the research object to carry out aerobic endurance training. Nanoselenium and placebo were supplemented in each group. The evaluation model of nanoselenium on aerobic endurance exercise was established by system control method, exhaustion compensation method, and analytic hierarchy process. The adaptive changes of nanoselenium on aerobic endurance exercise of grey rabbits were studied in detail, and the effects of exercise and antioxidant on the body were observed. Compared with the previous research methods, the difference is that the decentralized control theory is introduced as the guiding ideology of the research. According to the experimental results, the accuracy of the overall experimental results is improved by about 20%, and the accuracy is higher, which has certain practical value.