Retraction] Kinematic analysis of success strategy of YANG Hak Seon technique

Abstract

[Purpose] The purpose of this study was to compare Yeo 2 vault and YANG Hak Seon vault to verify the possibility of YANG Hak Seon vault. [Methods] The YANG Hak Seon vault and Yeo 2 vault performed by five Korean national gymnastic athletes, and the photographic images were collected using a high-speed camera and their kinematic characteristics were analyzed by 3D image analysis. [Results] The main variable of the post-flight phase S1, S4, and S2 were similar to YANG Hak Seon vault. S1 showed the largest at shoulder angle and the highest body center of mass at horse take-off. S4 showed the smallest shoulder angle at horse take-off, slow twisting at the post-flight ascending period, but faster femoral rotation during horse contact. S2 showed the slowest twist velocity in the ascending period of the post-flight and the smallest rotational distance and twist distance at the peak. S3 showed the slowest horse take-off velocity, the least time in the post-flight phase, and the hip joint was flexed at the peak. [Conclusions] S1 is required to increase the twist velocity by narrowing the shoulder angle during post-flight. S4 is required to strong push-up and an increase in the twisting velocity in the post-flight ascending period. S2 is required to shorten the horse contact time and increase the horse take-off angle through powerful femoral rotation after board take-off. S3 will have to get enough power from the preparation phase.