Kinematics And Semg Analysis Of The Axe Kick Technique Of The Elite Female Taekwondo Athletes

Research purposes:In this study,11 female Taekwondo athletes from Shanghai Institute of physical education were analyzed in terms of the biomechanical characteristics of their right leg and left leg.The kinematic and EMG data of the athletes were obtained by using vicon infrared camera technology and Delsys EMG system.This paper analyzes the kinematic data of each link of the swinging leg and the supporting leg and the characteristics of the electromyography of the movement when the athlete completes,explores the relationship between the kinematics and the surface electromyography,and then analyzes the relationship between the joint angle of the athlete and the changes of muscle activity.research method:Vicon and Delsys were used to simultaneously collect the undercuts of 11 subjects.The obtained kinematics raw data were processed by American VISUAL3 D software(Visual3D Version 3.34.0),and EMG data were processed by EMGworks EMG analysis software.Finally,EXCEL software and Origin7.0 software were used for statistical analysis and mapping of the data.Research result:(1)In terms of the displacement of the center of gravity of the athlete's body,the Yaxis(sagittal axis)has a large moving distance,and the X-axis(coronary axis)has a small moving distance.(2)The order of displacement of swing leg is toe> ankle> knee> hip.The relationship between athletes' height and joint displacement is not proportional,and it is the same as previous research results.(3)The general trend of the hip joint angle of the swinging leg is decreasing-increasing,the change of the hip joint angular velocity is increasing-decreasing-increasing-decreasing,and the knee joint angle and the angular velocity are decreasing-increasing.-Reduction.The research results of hip and knee joint angles are similar to those of previous studies.The change of ankle joint angle in this article is the increase-decrease-increase.(4)Concerning joint speed,compare the results of previous studies: knees,ankles,and toes have peak speeds during the knee lift stage,and there are two peaks in the whole splitting process.During the kicking stage,the ankle joint is faster than other joints.The speed is large,and the change of the hip joint speed is small during the whole splitting process,and the change becomes stable.The research in this paper is similar to the previous research.(5)The peak value of the hip angle of the supporting leg appears during the knee raising phase,and the peak value of the angular velocity appears during the kicking or leg retracting phase.The peak value of the knee joint angle and the angular velocity occurs between the knee raising and the kicking phase,and the peak angle of the ankle joint It appears in the range from the end of the knee-raising stage to the beginning of the kicking stage,and the peak value of angular velocity appears in the kicking stage.For the analysis of the support legs,the previous people mainly explained the reasons for the length of the swinging legs and the reasons of the hit points through the changes of the support legs' rotation,lifting and sliding forward.(6)The three muscles,the left biceps femoris,the left gluteus maximus,and the left rectus femoris,reach the EMG peak first,and the tibialis anterior muscle finally reach.The results of the left gluteus maximus and the left biceps femoris are similar to those of previous studies,illustrating the importance of supporting the leg(left side)to maintain body balance.The right latissimus fasciatusis,right rectus femoris,and right tibialis anterior muscles are muscles with large contribution values,integral electromyography,and root mean square amplitude results.The same result as previous scholars' research is that the latissimus fasciae extensor muscle has the largest integral EMG value.Analysis conclusion:(1)In the whole process of splitting,the period of leg collection is the longest.(2)In the analysis of the center of gravity displacement,the athlete has the largest distance of the center of gravity displacement on the Y axis(sagittal axis),the smallest distance of the X axis(coronary axis),the larger the distance of the Y axis is beneficial to the offense,and the smaller the X axis displacement indicates the athlete's control it is good.(3)From the angle and angular velocity changes of the swinging hip,knee,and ankle joints,it can be seen that the angles of the three joints reached the minimum value at the end of the knee raising phase and the start of the kick target,and the peaks of the three joints were all in the kick target phase..(4)There are two peaks in the velocity values of the knee,ankle and toe of the swinging leg,and the trends are similar.The peaks of the speed of the knee and ankle shut down and the toe are all at the knee raising stage.The maximum speed.(5)The maximum angle of each joint of the supporting leg appeared in the knee-lifting phase,and the peak value of the angular velocity of the three joints appeared in the kicking phase,and the knee flexed during the knee-lifting and reducing phases of the support leg.(6)The right latissimus fasciae,right rectus femoris,and right tibialis anterior muscles have a large amount of electrical discharge and a strong ability to recruit muscle fibers,as well as a strong ability to coordinate muscles.(7)The left gluteus maximus,the left biceps femoris,and the left rectus femoris have a certain relationship with the peak kick velocity.