Kinematic Analysis Of The Rhythm Characteristics Of Throwing Steps And Final Exertion Techniques Of High-level Javelin Athletes In My Country ——Taking The Top 8 Men’s Athletes In The "Zhaoqing Station" Of The National Athletics Gr

Research purpose: by analyzing the video data of China’s elite javelin throwers,this paper reveals the kinematic principle and law of javelin throwing step and final exertion technical rhythm,so as to provide a theoretical basis for improving the javelin technical action rhythm,so as to obtain a longer distance and better performance of javelin,and also provide theoretical cognition of rhythm for Javelin Training and teaching,hoping to improve the technology of Chinese male javelin throwers on rhythm.Research methods: this research adopts the methods of literature,investigation and interview,three-dimensional video shooting,etc;The high-speed shooting technology was used to take three-dimensional photos of the top 8 Javelin Athletes in the final of the national track and field Grand Prix,and the simi motion3 d software was used to analyze the video.The relevant factors affecting the javelin technical rhythm,such as the step length,step time,body center of gravity speed,joint angle and angular speed in the throwing step and the final exertion stage,were analyzed.Through the comparison and analysis of the data and graphics of 8 athletes,the technical rhythm characteristics in line with the characteristics of Javelin events are summarized.Research conclusion:1.the speed rhythm of the whole process of the final exertion of the throwing step:（1）the speed of the center of gravity of the human body presents two stages: first,the speed is maintained,and then the speed continues to drop until the javelin leaves the hand after the left side is quickly braked;（2）The average javelin speed of the eight athletes in the seven phases T1-T7 is 5.94m/s,6.57m/s,5.87m/s,6.11m/s,9.62m/s,13.73m/s and 26.91m/s respectively,showing two stages: the first is to collect momentum in the T4 phase,the second is to collect momentum in the t4-t5 period,and the T7 reaches the peak,showing the rhythmic characteristics of explosive force.2.technical rhythm of throwing steps: eight elite athletes took four steps of throwing steps（1）the stride showed the law of one large,two middle,three largest and four smallest strides;（2）The step time showed the rule of "one two short","three long" and "four shortest";（3）The rhythm of gait frequency showed the law of one fast,two fast,three slow and four fastest;The first two steps are mainly to ensure the speed and stabilize the gun.The third step is to lengthen the work distance for better transmission of kinetic energy and better surpassing instruments.The last step is to use small steps to quickly brake and ensure the height of the center of gravity to improve the height of the hand.3.technical rhythm of final exertion:（1）the rhythm of upper limb presents the characteristics of explosive exertion rhythm of recruitment,which is found after T6 phase,and the right shoulder drives the right elbow;（2）The rhythm of lower limbs shows the following characteristics: the kinetic energy of lower limbs is transmitted upward from buffering to pedaling and stretching.The pedaling and stretching of right knee occurs before T6 phase,the pedaling and stretching of right hip is similar to that of right shoulder,and finally the pedaling and stretching of left knee;（3）Finally,the exertion sequence of the exertion technique is the rhythmic characteristics of collecting explosive force,that is,right knee buffer left knee buffer right knee push extension right hip push extension right shoulder sudden increase right elbow sudden increase left knee push extension.