The Sport Biomechanics Analysis Of Rizi Pounching In Wingchun

Research objectives: To work out the velocity, angles, angular velocity, angular acceleration, intramuscular discharging sequence , IEMG and RMS by using the methods of Kinetics, Kinematics,Bioinformatics that can show how punching of Jinli in WingChun. The paper is not only exploring the secret of WingChun explosive force but giving the clue for researching Jinli of Chinese traditional Kongfu.Research methods: Three WingChun practitioners are punching three groups and three times per group . The instruments included two high-speed cameras, force plate and the device of myoelectricity. The angle of 3D photography is 45°and distance is 10m by two Phantom v4.0 high-speed cameras Vision made in Research Company. The principal optic axis across angle is about 90°, frequency of sampling is 125Hz. One Sony camera is following filming with Dartfish video analyses software. The ground reaction force, the speed and acceleration of foots when subjects moving according on Z axis on force plate are tested by KISTLER force plate, made in Switzerland, and the frequency of sampling is 1000Hz with Application Software Version:3.2.6.104. Before the iEMG dates is captured by device of myoelectricity with 16 channels , made in Germany, the amplificatory rate is 1000, and the Low-Pass Filter is 20Hz, High Pass Filter is 450Hz, then the dates are analysed by DasyLab10.0 software.Research results: Protecting and attacking the medial line of the body is one of the fundamental principles in WingChun. The training level, the length of arms, the width and the flexibility of shoulders of practition- ers are the main courses that influence subjects accord on the rule. The paper uses the right shoulder-chest angle to make sure subjects obey the rule or not. The practitioner of 4 years training is more better than others on controlling body balance and punching more power on using the force from the lower limbs by adjusting the pose when they are standing suppressing horse stance. Though all subjects used the waist when they are pounching, but only the angles of waist, knees, suppressing horse stance of 4 years training practitioner show remarkable differences, the paper believes that is the one of courses why the high training level WingChun master can punch more powerful explosive force.Because of the personal habit the subjects refer to right knee or left one, when they are punching . The paper believe that the habit is advantage for punching explosive force. The most speed and acceleration of punching do not appear the same time, when subjects punching, but the 4 years training practitioner's most powerful punching is the first, the most momentum is the second . The most speed, the mean acceleration and the mean speed of right elbow is more slowly than right fist. The mean acceleration represents that the elbow is a speed-down process. The sequence of muscles contractions is different among subjects, and that represents the sequence of generating force is different. Musculi triceps brachii is the source of punching power, the biceps brachii is making the fist back, and the main function of other muscles is fixation joints to against injure and keeping good posture that is best for torque and momentum moving when punching. Some muscles are discharging electricity together with musculi triceps brachii, it is the key to explosiving force.Both the methods of punching and the number of muscles who favorite make the sequence of discharging electricity different, and influence the explosive force of WingChun. The RMS of musculi pectoralis major is not more than musculi triceps surae, but other muscles'are very different. The practitioner of 4 years training is better than others on harmonizing counteracted muscles and using muscles of lower limb. Research conclusions: The first, suppressing horse stance is used to enhance stability of lower limbs and keep body balance, it is advantageous to discharge explosive force by reaction propulsion from ground with adjusting of whole body angles. The second, the most speed and acceleration of punching do not appear the same time, when subjects punching, but the most powerful punching of the 4 years training practitioner is the first and the most momentum is the second. The third, musculi triceps brachii is the source of punching power, the main function of other muscles is fixation joints to against injure and keeping good posture that is best for torque and momentum moving when punching. The fourth, how many and where the muscles constriction with musculi triceps brachii is crucial on explosive force.