Building the Mechanical Model of Lower Limb Muscle Strength of Adolescent Athletes in Track and Field

Abstract

The purpose of this study is create a theoretical basis for improving the lower limb muscle strength of adolescent athletes in track and field by building a mechanics model of vertical jump in situ of adolescent athletes in track and field. 77 subjects were involved in this test and performed the SJ and CMJ test, respectively. The Portable Kistler9286AA Measuring Force Platform is used to test the vertical jump in situ. A 3-D movement analysis was performed by a six-camera Vicon MX-system. Subsequently, jump height, knee joint range of motion were analyzed. Kinematics and dynamics parameters were obtained in SJ test and CMJ test. Through one-way analysis of variance, we found that the centrobaric height of subjects reached maximum when they were about 90 degrees knee flexion (P<0.01) in SJ test, the mechanical equation was finally determined by correlation analysis and regression analysis. Mechanical equation: y=-3.426-0. 319x(1)+1.718x(2)+8.289x(3) (y=centrobaric height, x(1)=angular acceleration, x(2)=initial velocity, x(3)=knee joint angle).