• L. Ging
  • L. Jin
  • Y. Gau


INTRODUCTION The last few steps are very important in the broad jump approach. No matter what approach rhythm is adopted, jumpers must reach the highest speed in the last four steps. The speed that jumpers reach is an important standard for effective jumping. Man have been studied the most but few of women jumpers have studied. By examining three excellent women and men broad jumpers, a search for differences between women and men broad jumpers can afford a theoretical basis for coaches and athletes to grasp reasonable sport skills. METHOD Three excellent women and men broad jumpers were studied. The high speed cameras [model: PHOTO SONICS] 16 rnm speed 100 framers per second U.S.A. model was used. Main shaft of the cameras was vertical in order to collect approach and take-off position in the last four steps. Horizontal velocity, vertical velocity, stride, and step frequency in the last four steps were analyzed. The data camera was processed by film analyzer model: NAC MWTAS 100). RESULT Women were 8.7 meter per second and men were 10.0 metre per second for average value of horizontal speed. Women not only differ from men in approach speed but also in take-off strength. Men were about 50 percent larger than women in instantaneous power. The largest instantaneous power depended on muscular contraction speed and strength. By examining the knee joint, men had 62.5% larger muscle strength and 98.2% higher contraction speed. Men differ from women in the instantaneous power, the key is in muscular contraction strength. Stride and step frequency in the last four steps were showed that maximum stride of women and men occurred on the second to last step but minimum stride occurred on the final step. They properly lowered their centre of gravity at the second to last step, so that they can gain larger vertical velocity during take off and increase vertical working distance. So they must increase stride at the second to last step. CONCLUSION The second to last step of women and men broad jumpers was bigger than the final step. It showed rational technique of the transit of approach to taking off. It made the broad jumper maintain higher horizontal velocity at the same time gain bigger vertical velocity and raise taking off effect. We think it is necessary that women's horizontal and vertical velocity be increased during take off and to properly increase their stride at the second to last step and to decrease p the final step in order to raise women's jump standard. This is the way to shorten the gap between women's and men's results. Ideal take off should not give up horizontal velocity in order to exchange for vertical velocity. If take off movement compromises horizontal velocity too much, it causes loss of height in the jump. During take off the leg can not bend too deep in order to conserve explosive strength. Minimum value of horizontal velocity in the last four steps are greatly different, women had a tendency towards the last four steps but men is tendency towards the second to last step.
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