Biomechanical Analysis Of Zhao Pengchuan's Hurdle Clearance Technique For Men's 110m Hurdles

Men's 110 m hurdles is always a hot item in sports.Especially the appearance of Liu Xiang,the "Asian flying man",has promoted the development of hurdles in China.It has also made Chinese scholars take a new height in the study of men's 110 m hurdles.Since Liu Xiang retired,there are only a few of athletes who can enter the finals on this item in international competition.The top priority now is how to make some of our country's outstanding athletes rank among the top in the world,narrowing the gap between Chinese hurdler athletes and outstanding players in the world.In this paper,three-dimensional video analysis system,surface electromyography test system,and three-dimensional force measurement system were used to simultaneously test the athletes(Zhao Pengchuan,master-sportsman,the fourth men's 110 m hurdles in the 2017 National Games,the best score: 13.83s).The data obtained were statistically processed,and the techniques of combining the kinematics,dynamics,and surface myoelectricity were used to analyze the techniques of excellent hurdlers in China,in order to provide references for improving technical movements and improving training results.Research conclusions: 1)Kinematics conclusion: During the take-off stage,compared with Olympic champion Liu Xiang,Zhao Pengchuan's landing angle(60.47°)is relatively small,and the minimum knee angle(39.48°)is larger than the Olympic champion Liu Xiang.The cross-angle(67.75°)is not ideal,and there is no significant difference in knee joint angle(159.03°)at the moment when the take-off-leg's tiptoe leave the ground.At the moment when the right foot toes off the ground,the horizontal velocity of the center of gravity(8.93m/s)is small,and the vertical speed(1.71 m/s)is slightly larger;the center of gravity(10.45°)is larger and the stage is longer(0.11s).During the launching satge,the maximum body rake angle(42.38°)has reached the modern hurdle technical requirements.The maximum leg angle(119.90°)is too small,and the span distance(2.16m)and the underbar distance(1.36m)are moderate;the step length(3.53m)of the hurdle is slightly smaller;the S1/S(61.32%)is slightly smaller,and the phase time(0.38s)is longer.During the landing stage,the grounding angle(77.68°)is too small.At the moment when the knee toe start landing,the joint angle(171.49°)is too small,and the knee joint angle(174.02°)is too small for the vertical support;the depression angle(62.49)°)is larger;the trunk anteversion angle(8.99 °)is too large and the period(0.113 s)is slightly longer.2)Surface electromyography test results: Zhao Pengchuan's muscles were involved in the work at each stage during the men's 110 m hurdle.The percentage of muscle contribution was known as: fascia tensor(25.37%),biceps femoris(22.51%),gluteus maximus muscle(16.61%)and the tibialis anterior muscle(14.90%)were the major force-generating muscles during the take-off stage,and the rectus femoris muscle(10.34%)and the gastrocnemius muscle(11.26%)had relatively less effect;The fascia lata tensor muscle(22.92%)and rectus femoris muscle(19.02%)are the main force-generating muscles in rising phase;the gluteus maximus(17.28%),biceps femoris(16.57%),gastrocnemius muscle(11.27%)and tibialis anterior muscle(12.95%)are relatively small;the gluteus maximus(28.06%),biceps femoris(22.07%)and gastrocnemius muscles(14.99%)are the main force-generating muscles during the descending phase.The fascia lata tensor muscle(13.33%),rectus femoris muscle(11.83%)and tibialis anterior muscles(18.96%)have relatively small effects.The gluteus maximus(25.19%),biceps femoris(22.10%)and gastrocnemius muscles(18.96%)are the main force-generating muscles at landing stage.The musclar(12.83%),rectus femoris(11.45%)and tibialis anterior muscles(9.46%)are relatively small.3)The conclusion of dynamics analysis during landing stage: The Fz curve of the vertical force component during the left foot landing phase first increases,then decreases,then gradually increases to reach the peak value,and then slowly decreases.The dynamic Ft curve shows a double,and the peak curve shows that when the toe of the left foot passes through the buffer after the first peak,it immediately turns into the extension;the Fx curve also follows this rule in the positive direction,but the absolute number of negative peaks(1266.75N)of the extension is smaller than positive peak(1759.25N);Fy peak and integral area are basically positive,indicating that the athlete's body is a bit tilted.