The Kinematics Analysis On The Difficulty Elements Butterfly Jump Family Of Aerobic Gymnastics

The difficulty of competitive aerobics is an important standard to measure the skill level of the athletes and also the core competition factor for the competition.Following the 2013 edition of aerobics international grading rules,with Chinese characteristics will be the first time the Butterfly Jump Family included in group C after difficult,a new cycle significantly enhance 2017 edition rules of Butterfly Twist difficulty score,which means that the Butterfly Jump Family is one of the orientation of new cycle rules difficult.Difficult competitions at home and abroad of Butterfly 1/1 Twist Ed rate is higher,and there is no complete 1.0 high score of Butterfly 2/1 Twist difficulty,aerobics areas did not see the scholar study of Butterfly Jump Family difficulty,to improve teaching and training reference,climbing higher difficulty lay the foundation,the group characteristics of the key technology of difficulty parsing is an important part of the unknown.In this study,we used the method of literature,interview and experiment to capture the system by using the infrared light spot high-speed motion capture system,high-speed acquisition hu bangda difficulty Butterfly and Butterfly 1/1 Twist movement kinematics data,analysis of Butterfly and Butterfly 1/1 Twist technical characteristics,and compare the two analysis,to explore the key technical features of this group of difficulty movement,promote the diversified development of the aerobics movement.Conclusions:1.In the starting and jumping stage of the Butterfly,the knee bends less,and the lower part of the body bends to the left side of the head.Single pedal stretch stage shoulder,hip in the horizontal plane torsional amplitude is bigger,strengthened the ability body around the sagittal axis rotation,and to the right shoulder hip projection Angle tends to be linear,right hip Angle is 122.5 °for power is appropriate timing.2.The Butterfly is kept parallel to the ground during the air phase,with a certain braking,and the rotation span of the hip joint is large,reaching the minimum of the leg Angle at the peak of the center of gravity;In the landing stage,the air leg needs to move sideways to the horizontal direction.3.The Butterfly 1/1 Twist in the takeoff phase also is given priority to with hip flexion,single pedal stretch to the right hip horizontal projection Angle tends to be linear,power is right hip Angle 140°for appropriate timing,off the ground before swinging leg and torso approach on the same axis,is advantageous to the subsequent phase suspension rotating around its vertical axis.4.At the beginning of the Butterfly 1/1 Twist leaps through prerotation increase velocity of shoulder,hip,with arms and legs to its vertical axis to reduce the turning radius,reduce the loss of kinetic energy.The torsion degree of the shoulder hip is large and the shoulder is the dominant rotation.The landing leg load is large,the upper body should avoid premature lifting.5.Butterfly in overall motion speed is less than Butterfly 1/1 Twist,mainly reflected in the horizontal plane speed,velocity difference is small,vertical direction of the points to the center of gravity height change trend quite.6.At the beginning of Butterfly,at a time of take-off from the ground speed is less than the Butterfly 1/1 Twist,and Butterfly takeoff Angle is bigger,preference for vertical takeoff,the takeoff stage body torsional amplitude,closely related to the direction and speed of the swinging leg;Both in the speed of the landing point,landing on the legs,hips and shoulders torsion Angle difference,prompting Butterfly twist degree of Butterfly 1/1 Twist is bigger.