Kinematics Analysis Of Throwing Technique Of Excellent Cheerleader Base Athletes In Sichuan Province

Cheerleading has become one of the mainstream sports methods in campus sports in China.Cheerleading exercises not only provide a lively and healthy means of exercise,but also promote mutual communication,learning and competition between campuses.Competitive cheerleading is divided into dance cheerleading and skill cheerleading.Throwing technical moves is one of the most important,typical and technically most difficult technical actions in cheerleading.This article mainly uses the experimental method,three video analysis method and mathematical statistics method to perform three-dimensional video analysis of the two sets of athletes with different horizontal bases.It describes the movement trajectory of the upper and lower limbs of the two groups of athletes and collects the angles of important joints Angular velocity change data.The experimental data were expressed as mean ± standard deviation(X ±SD),and analyzed by independent sample T test,p <0.05(*)was a significant difference.Research result:(1)The total time consumption between the two groups is similar,and there is a significant difference between the sinking phase and the emptying phase.The high-level group spends less time in the sinking phase than the non-high-level group and the time spent in the emptying phase is greater than the non-high-level group.(2)There is no significant difference in horizontal displacement between the two groups during the whole process of straight throw,but the center of gravity and upper and lower limbs of the high level group are in the horizontal direction(x-axis,y-axis direction)and vertical direction(z-axis)(Direction)offset distance is less than the non-high level group.(3)There were significant differences in the angles of the shoulders,hips,and knees between the two groups during the racking and sinking stages.The high-level group's shoulder joint angle was smaller than the non-high-level group,and the hip and knee joint angles were larger than the non-high-level group.There was a significant difference in the shoulder joint angle between the two groups during the uplift phase.The shoulder joint angle in the high-level group was smaller than that in the non-high-level group.There was a significant difference in the hip and knee angle between the two groups in the cradle stage.The hip and knee joints in the high-level group were significantly different.The angle is larger than the non-high level group.(4)There was a significant difference in peak angular velocity of the shoulder joint between the two groups during the emptying phase.The peak value of the angularvelocity of the shoulder joint in the high-level group was greater than that of the non-high-level group.There was a significant difference in the peak angular velocity of the hip joint between the two groups in the upswing phase.The peak value of hip angular velocity was smaller than the non-high level group;the peak value of knee angular velocity between the two groups was significantly different during the shelves,and the peak value of knee angular velocity in the high level group was greater than that in the non-high level group.Analysis conclusion:(1)The high-level group base athletes in the high-level group have larger hip and knee joint angles,smaller shoulder joint angles,rapid adjustment of vertical displacement,and lower movements of the upper limbs and torso as long as the movement of the lower limb structure is achieved,which is a good guarantee.The stability of the center of gravity when dumpling athletes are on the shelves,and can connect the next stage of movements more consistently.In contrast,the non-high-level group has a low squatting position,large upper limb and trunk movements,and insufficient stability.(2)In the sinking stage,the hip and knee joints of the high-level athletes of the high-level group sink rapidly and at reasonable angles,and the angle of the shoulder joints is small,which can ensure the stability of the elite athletes while exerting the maximum kinetic energy.Non-high-level athletes sink too low,the angle of shoulder joint sinking is obvious,and horizontal displacement is prone to occur.(3)The peak angular velocity of the hip and knee joints of the high-level athletes in the upper-throw group is not as large as that of the non-high-level athletes,but the force lasts longer and the angle of the shoulder joint is more reasonable.The peak angle of hip and knee angular velocity of base athletes in non-high level group is short,but the duration is short.(4)There is no obvious difference between the two groups of athletes in the vacant stage.Each joint stretches and stretches,and the longest cushioning distance is pursued,which has a better cushioning effect.(5)In the high-level group of the cradle stage,the hip and knee joints have larger angles and higher squatting positions,which can better connect the subsequent movements faster and slightly abandon the best cushioning effect.In the non-high-level group,the hip and knee angles are small and the squatting position is too low.