Abstrait

Study ofwhip leg effects based on biomechanics and its application

Guofeng Liu

Make Chinese Sanda athletes to improve self skills effectively, this paper results in potential energy generated by whipping legs, by analyzing mechanical and dynamic relationships. Besides, propose the angular velocity of left thigh depends on hip joint angular velocity and waist speed while whipping leg, the angular velocities of knee joints and left thigh decide angular velocity of calf. Diving buckling degree of left thigh and left calf in preparation must be less than 45°and keep the angular velocity of calf greater than that of thigh to help accelerate knee joint. In the whip-leg stage, folding legs reduces inertia momentum, increasing angular velocity of knee joints effectively. Besides, it helps contract muscles, to keep best state to generate strength of legs and increase contract speed. In the whipping legmodel, the principle conforms tomomentumprinciple.Athletes can increasemomentumof knee joints through braking effect of knee joints, then transferring to hip joints, to get end accelerations. The results provide the practical advice for athletes