The Study Of Isokinetic Contraction Effects Of Knee Flexors And Extensors With Hip At Different Flexion And Extension States

Objective: This study tried to find the interaction between knee and hip with their best motionperformance by analyzing isokinetic test indicators of knee flexors and extensors with hip atdifferent flexion and extension states in order to enrich related fundamental researches and serveathletes training.Methods: This article used ISOMED2000isokinetic test system made in Germany to test theindicators of knee extensors and flexors, with hip at different flexion and extension states.Theobjects of this study are ordinary university students from our school. It choosed60°/s，120°/s，180°/s for concentric contraction test and20°/s,60°/s for eccentric contraction test.Results:1.In the concentric contraction mode: when hip is at certain flexion and extensionangle,the peak torque,body weight of peak torque,max work and total work of knee extensorsand body weight of max work,max power,average power of knee extensors and flexors areP<0.05with the speed increasing. With the increase of hip flexion and extension angle, the peaktorque, body weight of peak torque, angle of peak torque, max work,total work, body weight ofmax work,max power,average power of knee extensors and flexors are P<0.05.2.In the eccentriccontraction mode: when hip is at certain flexion and extension angle,the body weight of maxwork of knee flexors and max power,average power of knee extensors and flexors are P<0.05with the speed increasing. With the increase of hip flexion/extension angle, the peak torque,bodyweight of peak torque, angle of peak torque, max work,total work, body weight of max work ofknee flexors and max power of knee extensors and flexors are P<0.05.Conclusions：1.In the concentric contraction mode: when the hip is at certain flexion andextension state,there are significant differences among the indicators of knee extensors with thespeed increasing. And there are significant differences among the indicators of knee flexors withthe increase of hip flexion and extension angle.2.In the eccentric contraction mode: when the hipis at certain flexion and extension state, there are significant differences among maxpower,average power of knee extensors and flexors and the body weight max work of kneeflexors. And there are significant differences among the indicators of knee flexors with theincrease of hip flexion and extension angle.3.Most indicators are optimal when the hip is at90°,which means the optimal athletic effects will ensue.Recommendations:1.The objects should take part in more physical exercises.2. The study may provide theoretical basis for the evaluation of rehabilitation.3.The speed selected in thisexperiment is less in the eccentric contraction mode.So we propose to increase more speeds forthe experiment.