In order to explore the effect of leg swing in Wushu Sanda, a method based on multimedia medical big data is proposed. The joint torque of hip joint is less than that of healthy subjects. The peak values of the horizontal and vertical components of the joint reaction force are approximately the same as those of the sound subject, and a comparison is made between the two kinds of leg swing strike effects of Wushu Sanda to select the leg swing strike which is more suitable for Wushu Sanda. These results show that the turning strategy of Wushu Sanda on the stairs can be used to swing the legs after turning with similar or smaller hip joint dynamics. Multimedia medical big data analysis has the greatest impact on the variability of simulation dynamic parameters. Six test students turned their knees and turned their heels forward, which is better than the technology without turning their knees and turned to swing their legs in the air. At the moment of striking, the running track of the front striking feet in the air is generally shorter. Therefore, the technology of turning their knees and turning their heels forward has higher concealment and better striking effect. It is proved that the research results may improve the inertia and usability of Wushu Sanda process design.