The Asymmetry Of Lower Limb And The Biomechanical Performance In Single-leg And Double-leg Jumping

Purposes: First, the paper analyzes the relativity about five assessment method of26subjects.Then select the optimal evaluation methods of this paper, with the bestmethod of hopping, this paper divide legs into dominant side and non-dominant side.Further research the biomechanical performance of the dominant side and non-dominant side in different forms of jumping.Methods:Slected26healthy male students unkonwn the aim of experiment whocomplete the motions involved bilateral single-leg forward jumps(single hop), singlevertical jump(SVJ), double forward jump and double vertical jump. The kinematic datawere captured by VICON motion capture system and the dynamic data were recordedby KISTLER force plate. The results exported in the form of number matrix of ASCII.The experimental calculations and pictures were customized by MATLAB. Using apaired T-test to compare the biomechanical indectors of bilateral limb.Results: The five methods that assess dominance are effective. There is only astrong positive correlation between single-hop and SVJ, the strong negative correlationbetween SVJ and concentrate extensor, the strong negative correlation betweenconcentrate flexor and concentrate extensor;(2) By the method of single hop assessingdominant leg, the comparison of results showed significant differences in the highestpoint on the center of gravity, the lowest point on the center of gravity, the bufferdistance, the vertical distance, the maximum angular velocity of the hip, the peakground reaction force of anteroposterior direction, the average ground reaction force ofanteroposterior direction, the impulse of vertical direction between dominant leg andnon-dominant leg in single vertical jump; Significant difference were also found inanteroposterior, mediolateral, vertical displacement, maximum angular of hip and theimpulse of anteroposterior between dominant leg and non-dominant leg in single hop jump;(3)By the method of single hop assessing dominance and non-dominance, there isonly significant difference of the time of the peak ground reaction force betweendominant leg and non-dominant leg in double-leg jump.Conclusion:(1) There are differences among the five methods that assessdominant-leg and non-dominant leg. It’s necessary to reasonable select the methodbased on the content study.(2) The differences of dominant leg and non-dominant legare not same between the single-leg and double-leg movement may be mainly affectedby the muscle strength, nerve innervation and action structure.