Kinematic Analysis Of Difficult Movements In Rhythmic Gymnastics Penché

Research purpose:Rotating technique is a key technical action in artistic gymnastics,which has strong ornamental and competitive nature,and is one of the important difficulties that reflect level of athletes' competitive ability.At present,in the measurement,analysis and evaluation of sports technology,the kinematics three-dimensional camera test research method is the most commonly used,which is divided into normal speed shooting and high speed shooting according to the shooting frequency of the camera.In this paper,the three-dimensional infrared high-speed camera test method is used to collect the Penche(backward vertical rotation)movements of Chinese excellent rhythmie gymnasts and analyze the kinematics of technical movements at various stages.It aims to provide a reference for the practical training of the rearward vertical rotation technology..Research method:This research takes the vertical rotation of the split leg after artistic gymnastics as the research object.Use research methods such as experimental methods,literature methods,mathematical statistics methods,and expert interviews.The Qualisys Motion Capture Systems infrared high-speed motion capture system(8 sets)was used to shoot the Penché difficulty of 8 excellent rhythmic gymnasts and synchronously collected kinematic data at a frequency of 200 Hz.Use Visual3D software to construct the human body model and calculate the three-dimensional kinematics index.Research results:Athletes in the swing phase increase the vertical velocity of the center of gravity,torso torso,and shoulder joint movement to store muscle elastic potential energy,which lays the foundation for the subsequent start-up phase;the maximum value of the horizontal rotation angular velocity of the upper right shoulder of the upper limb occurs earlier than the left shoulder(Between 0.7s left and 1.6-1.8s right),the short pause when the knee is turned to the right forces the second stage of force in this technical stage;the height of the center of gravity in the rotation stage is 0.47 times and 0.53 times the height.During the rotation,the angle between the legs is above 170°on average,which is more in line with the technical requirements of the rotation;the angle of the upper extremity joint during the landing phase changes more than the lower extremity,and the upper extremity assists the lower extremity to control the overall stability of the human body.Research conclusions:1.During the swing phase,lowering the center of gravity is conducive to athletes' ability to win.The body changes in the swing phase are mainly concentrated on the trunk and upper limbs.2.During the start-up phase,the body joints support the dynamic stability of the legs from bottom to top.The overall movements of the upper and lower limbs are complicated and not synchronized,and the upper limbs exert force before the lower limbs.The angle between the lower limb joint and the ankle joint determines the stability of the center of gravity at the end of the start.3.During the rotation phase,the height of the center of gravity gradually increases with the movement range of the trajectory,the smaller the movement range,the higher the stability.The height of the center of gravity is best between 0.76m-0.86m.The slight change in the angle of the shoulder joint on the right side of the upper limb determines the stability of the trunk.The angle change of the lower limb joint is a key index that affects the stability of the center of gravity.4.At the end stage,according to the technical characteristics of the landing technique,it can be concluded that the smaller the angle change of the athlete's lower limb joint,the higher the rotation stability.