The 2 High Horizontal Man Sportsman Run-up Final Step Sport Credits of Long Jump of Horizontal Speed Loss Reason

摘要

This paper compared relevant kinematic parameters of the long jump elites from home and abroad, it analysed the reason why the reduction of the horizontal velocity in the last two steps in the world elites was 0.48 m/s, while 0.68 m/s in the domestic elites. The first reason the paper presented is to jump up too early which leads to the decrease of the velocity in the last two steps, the second reason is that the accelerative ability is weak and the length of one step varies, and the third reason is that the landing angle of the last step is small but it is big for the angle of departure. Apart from the above mentioned reasons, the paper also proposed another indispensible factor is that, the change of the knee angle in the last two steps which can help prevent the horizontal velocity from deceasing.