Research Of Surface Electromyography Characteristics Of Forehand Pull In Table Tennis

Research purposes:Through the surface EMG capture and analysis system,this research hopes to collect and process the surface EMG signals of related muscles in the forehand pull up loop and down loop movements,and then compare the similarities and differences of the integral EMG value,root mean square amplitude value and muscle activation order of the two different movements,so as to clarify the origin of the forehand pull loop movement in table tennis Force mechanism and action law.Research methods:This study used Delsys trigno TM mobile(USA)surface electromyography acquisition and analysis system,combined with mathematical statistics and logical analysis.The surface electromyography(sEMG)data of forehand pull of 10 national first-class table tennis players from Beijing Sport University were collected.The collected data were processed by filtering,rectifying and righting.Then the integral EMG value,root mean square amplitude value,muscle activation sequence and muscle contribution rate were calculated.After interpolation by Origin9.0 software,the data were sorted and statistically analyzed by Excel 2016 and SPSS 17.0.Results:(1)There is no obvious difference in the activation sequence of the two movements,which conforms to the principle of human dynamic chain,but there are differences for individual muscles.(2)The total integral EMG value of forehand pull-down loop is greater than forehand pull-up loop.Biceps brachii,triceps brachii and brachioradialis brachii have higher integral EMG values in the process of two kinds of table tennis forehand loop pulling action,which indicates that the above three muscles have large discharge and play a major role in the action.The change rate of discharge amount of middle trapezius,bilateral rectus abdominis,right lateral oblique abdominis and left erector spinae involved in the two movements was greater.(3)There were significant differences in the integral EMG values of the right rectus femoris,the right rectus abdominis and pectoralis major,which indicated that the difference in the discharge of the three muscles had a great impact on the two forehand movements.(4)The left rectus abdominis,right erector spinae,deltoid,pectoralis major and biceps brachii collected more muscle fibers or changed more frequently in the forehand upward rotation loop.The rest of the muscles raised more units in the forehand spin.(5)There was significant difference in the RMS amplitude of triceps brachii muscle,which indicated that the degree of activation had a significant effect on the movement.(6)Biceps brachii was the most important muscle in the two movements.The muscle contribution rate of bilateral rectus femoris,left lateral oblique abdominis,right erector spinae,deltoid,pectoralis major,biceps brachii,triceps brachii and brachioradialis in the process of forehand pulling up loop is higher than that of forehand pulling down loop,and the difference of biceps brachii,triceps brachioradialis is more obvious than the other action.(7)The muscle contribution rate of right lateral oblique,bilateral rectus abdominis,left erector spinalis and middle bundle of trapezius in the process of forehand pull downward loop is higher than that of f-orehand pull upward loop,and the difference of bilateral rectus abdominis is more obvious than the other action.Advice:1.When learning and practicing the forehand pull up spin and pull down spin loop,we should follow the practice principle of human body power chain,and experience the transmission of force in the action.2.The muscle strength in the core area of the trunk is particularly important for maintaining the stability of forehand loop.In addition,the right lateral oblique muscle is the active muscle of rotating spine.Therefore,in the physical training of table tennis players,attention should be paid to the stability of the core muscles,the fast strength of the active muscles and the strength of the antagonistic muscles.3.More attention should be paid to the force of forearm in the process of forehand pull up loop;more attention should be paid to the stability of core area in the process of forehand pull down loop.