A Study On The Differences In The Speed And Power Output Of Barbell Squat Jumps Measured By Different Equipment

Research purpose: To evaluate the difference between linear position sensor(Tendo),inertial acceleration sensor(PUSH)and motion capture system(motion)to measure the speed and output power of barbell squats.Research method: Recruit 10 healthy male college students to perform two sets of barbell squat jump exercises with a weight of 20 kg and 30 kg repeated 6 times.Using the motion capture system(motion)as a reference standard,the linear position sensor,inertial acceleration sensor and motion capture system are used to simultaneously measure various indicators of the barbell squat jump;the longitudinal coordinate data collected by the motion capture system is used to obtain the instantaneous speed of the barbell through differentiation,Instantaneous acceleration and force,and then obtain the instantaneous output power,average speed and average power.Compare linear position sensor,inertial acceleration sensor and motion capture system to measure the difference between barbell squat jump speed and output power.Spearman correlation coefficient(r)and intra-group correlation coefficient(ICC)were used to analyze the correlation and consistency of the test results of the linear position sensor,inertial acceleration sensor and motion capture system;the paired t test and Bland–Altman diagram were used to represent the system Deviation;standard error(SEM)is used to represent the typical error of the measurement results;finally,the intra-group correlation coefficient ICC and coefficient of variation(CV)are used to evaluate the retest reliability of Tendo and PUSH.The level of statistical significance is set at P?0.05.Research results:(1)The correlation between the peak speed(20kg: r=0.968,30kg: r=0.976;p<0.001)and the average speed(20kg: r=0.843,30kg: r=0.845;p<0.001),peak power(20kg: r=0.850,30kg: r=0.814;p<0.001)and average power(20kg:r=0.829,30kg: r=0.845;p<0.001)of the barbell measured by the linear position sensor and the motion capture system under 20 kg and 30 kg loads is very high,but only the consistency between the peak speed is very high(ICC=0.927),the consistency between other parameters is low;(2)There is no significant correlation and peak value between the average power measured by the inertial acceleration sensor and the motion capture system under the load of 20 kg and 30 kg The correlation between power and average speed is low,and the consistency between the peak power,average speed,and average power measured by the inertial acceleration sensor and the motion capture system is low.Research conclusions:(1)There is good consistency between the peak speed measured by the linear position sensor and the motion capture device,indicating that the linear position sensor can accurately measure the peak speed of the barbell squat.(2)Neither the linear position sensor nor the inertial acceleration sensor is suitable for measuring the average speed,average power,and peak power of a free barbell squat jump.