Kinematic Analysis Of The Characteristics Of Close-body Fastball In Different Grades Of Volleyball Players In Some Colleges And Universities In Shaanxi Province

The contemporary volleyball match has entered the stage of comprehensive confrontation with high level,fast pace and high intensity.However,the main feature of near-body fastball is short distance,fast speed,strong holding capacity,and the purpose of sudden attack,so the effect of spiking and shielding is good.To prepare sound quick spiking technique is mainly composed of the air,run,jump,and fall to the ground five technology link action,every link of technical movement plays a vital and not to be sneezed at.Athletes want to occupy the initiative in the game,not only need comprehensive and skilled master the techniques,also coaches in athletes technical movements of the mistakes and unfavorable factors,thus to improve the athletes technical action,make the athletes technical moves further improve,so complete technical movement to make the attack to achieve the best effect.This article mainly at northwestern polytechnical university colleges and universities in shaanxi province level athletes(4)secondary athletes(4),xi 'an institute of physical education as research object,using literature study,expert interview method,the three-dimensional camera and other research methods,first and second class athletes men's volleyball in colleges and universities in shaanxi province sound analysis of the quick spiking technique of kinematics analysis.Based on the research results,the following conclusions are drawn:(1)In the run-up stage,there is an increasing tendency for the second-level athletes to run,which is not conducive to the observation of the passing of the ball.The last step of the second class athletes is smaller,and the running speed is slower,which is not conducive to running.(2)At the jump stage,the distance between the two feet of the first class athlete is greater than the distance between the two feet,which is conducive to jumping.At the beginning of the jump,the two athletes have an increasing tendency of ankle and knee joint,which is not conducive to the force of stretching.The distance between the two legs is less than the distance between the two feet,and the Angle of the left knee joint is increased when starting the jump,which is not conducive to the stretching force when jumping.(3)The main factors that determine the air stroke are: the height of the shot,the speed of the swing,and the reasonable relationship between the player and the ball position.The second-level athlete is not in good position with the ball during the jump,which is not conducive to the whipping of the swing.Firstand second class athletes have a low Angle of shoulder and elbow joint,and low point of hitting points.All of them are significantly different from the relevant data and theoretical analysis of the former scholars.The speed of each link in the right arm of the second level athletes from the elbow to the stroke is decreasing and the speed is not maximized.(4)Landing stage: the first class athlete USES both feet to land simultaneously.Most of the second-class athletes have a single foot landing,which can lead to ankle,knee and hip joint injuries.