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The purpose of this study was to quantify the contribution of body joints for take off of two-foot vertical jump performances with the increase of approach distance.Eight male taekwondo players volunteered to participate as subjects in two-foot vertical jump experiment with one-step, three-steps and five-steps approach distance.The take off phase of vertical jumps were filmed by using 16mm high speed camera and measured the ground reaction force by using the force platform simultaneously.At take off, a elapsed time of downward phase was shorter than that of push off, and also decreased the elapsed time of take off with the increase of approach distance.For the downward and push off phase at take off, the contribution of knee joint muscle group was increased significantly with the increase of the approach distance.However, the contribution of hip joint muscle group was decreased significantly with the increase of the approach distance relatively.The legs were the greatest contributors for two-foot vertical jump of each approach distance. The summation of the contributions derived from legs were about 90% for for downward and push off phase, respectively. And the contribution of the hip joint was about 50%. The results of this study indicate that while the legs contribution with the increase of approach distance were similar among one-step, three-steps and five-steps, the contributions of each joints of the legs employed to achieve these results were notably different.