Characteristics Of Isokinetic Muscle Strength Of Upper Limbs Of Tennis Majors And Its Correlation With Serve Speed

Research purposes:This study aims to test the isokinetic muscle strength index and service speed of College Male Tennis students,and analyze the correlation between the isokinetic muscle strength index and service speed.(1)explore the isokinetic muscle strength characteristics of upper limb joints of tennis students(2)This paper explores the correlation between the isokinetic muscle strength of upper limb and serve speed of special students,and compares the correlation coefficient between multiple activities of upper limb joints and serve,so as to provide targeted reference for tennis serve related special upper limb training.Research methods:11 male tennis postgraduates from Beijing Sport University were selected as the test objects.They were required to have more than four years of tennis training experience,master the basic tennis skills,be healthy and have no sports injuries.Use Isomed2000 isokinetic test system to test the isokinetic muscle strength indexes of shoulder joint flexion and extension,shoulder joint abduction 90°internal rotation and external rotation,elbow joint flexion and extension,wrist joint flexion and extension,and forearm pronation and supination.The test indexes were peak torque,relative peak torque,average power,relative average power and joint flexion extension ratio.The test mode was conc-conc.The maximum force of the test object was required,and the test angular velocity was slow(60°/s)and fast(180°/s)。The radar speed gun is used to test the service speed.The fastest service speed is required.Five effective services are taken in the right service court and the left service court respectively,and the average value of 10 services is taken as the service speed.SPSS 23.0 and Excel software were used to analyze the data,and the normality test was carried out on both sides of the isokinetic test results.The data meeting the normal distribution were compared by independent sample t-test,the data not meeting the normal distribution were compared by two independent sample nonparametric tests,Pearson correlation analysis was made between the results of isokinetic test and serve speed.Results:(1)Most of the peak torque indicators of shoulder abduction 90°external rotation,elbow flexion and extension,wrist flexion and extension,and forearm pronation and pronation in tennis events decreased with the increase of movement speed,but both shoulders The peak torque of joint flexion and extension and the peak torque of 90°internal rotation of shoulder joint abduction increased with the increase of angular velocity;with the increase of test angular velocity,the average power data of each joint muscle group increased.(2)The peak torque and average power of the special students on the holding side are higher than those on the non-holding side.Among them,the shoulder joint abduction 90° internal and external rotator group,elbow flexor group,wrist flexor group and forearm pronation and supinator muscle group There was a significant difference in the indicators on both sides(P<0.05).(3)The average flexion-extension ratio of shoulder joint flexion-extension peak moment is 76.77±2.6%,and the average power-average flexion-extension ratio is 101.01±2.29%;the average flexion-extension ratio of shoulder abduction 90° internal and external rotation peak moments is 111.36±7.02%,shoulder The average power flexion-extension ratio of 90°internal and external rotation of abduction is 137.1 7±5.94%;the average flexion-extension ratio of elbow joint flexion-extension peak moment is 87.79±6.3 1%,and the average flexion-extension ratio of elbow joint flexion-extension is 105.02±7.01%;wrist joint The average flexion-extension ratio of peak flexion-extension moment is 59.4±7.76%,the average flexion-extension ratio of wrist joint flexion-extension average power is 79.44±18.21%;the average flexionextension ratio of forearm pronation and supination peak moments is 100.84±10.38%,and forearm pronation and supination are average The power average flexion-extension ratio is 121.83±17.51%.(4)The slow 60°/s flexor and extensor peak torque index of the shoulder joint on the holding side is significantly or very significantly positively correlated with the serving speed.The average power of the slow(60°/s)shoulder joint extensor on the holding side is correlated with the serving speed.There is a significant and moderately positive correlation with the speed of the ball;the isokinetic index of shoulder joint abduction of 90°,internal rotation and external rotation is not significantly related to the speed of the ball;most of the peak torque indicators of the elbow joint extensor are significantly or very significant in height or in the ball speed.There is no significant correlation between the flexor muscles and the peak torque index of the wrist joint on the non-holding side.There is a significant or very significant moderate positive correlation with the serving speed;the forearm supination index of the holding side is significantly correlated with the serving speed.Or a very significant positive correlation.Conclusion:(1)among the joints of the upper limb involved in this study,the elbow extensor index has the highest correlation with the service speed,and the elbow is the main joint of the upper limb in tennis service.(2)The peak flexion and extension moments of most of the upper limbs of tennis students decrease with the increase of angular velocity,but the peak flexion and extension moments of the shoulder joints on both sides and the 90° pronation peak moments of shoulder joint abduction increased with the increase of angular velocity.(3)There are significant differences in muscle strength on both sides of the shoulder joint abduction 90°internal and external rotators,elbow flexors,wrist flexors,and forearm pronator and supinator muscles,and the holding side muscle strength is significant larger than the non-holding side.(4)Isokinetic muscle strength of slow flexion and extension of the shoulder joint on the holding side,isokinetic muscle strength of the elbow joint extensor,isokinetic muscle strength of wrist flexion and extension on the non-holding side,and supinator muscle strength of the forearm on the holding side are significant in terms of serving speed.Positive correlation.