Analysis Of Surface Electromyography Characteristics Of Standing Long Jump

Research purpose:The purpose of this study is to look through the standing long jump test methods of electricity and video synchronization analysis,combining with the knowledge of the anatomy and biomechanics,explore the standing long jump muscle power in different stages of the timing,duration of muscle power,integral electrical values and the rule of contribution,summarizes muscle electromyography features of standing long jump,the standing long jump special strength training and technical improvement is put forward reasonable Suggestions,enrich the theoretical system of the teaching and training.Research method:Use american-made Delsys Trigno ~TMM Lab all wireless methods of electric testing system,high speed camera and high performance laptop computer equipment to select 15 male students of guangzhou university institute of physical education(age 19.33±0.82,height175.13±4.88 cm,66.73±4.33 kg weight,grades are reaching more than 2.80 m)and standing long jump take-off,the empty and the ground three stage muscle acquisition of multi-channel semg.EMGworks Analysis software was used to process and analyze the collected emg signals,and the muscle activation time,inactivation time,integrated emg value and contribution rate were obtained.Conduct data processing and induction through WPS2018.Research results:1)during the buffer period of the take-off stage,the lower limb muscle group first stores elastic potential energy for work,which leads to the activation of the trunk muscle group and the upper limb muscle group;Rectus abdominis and external oblique are the key to stabilize the upper and lower limbs at the last moment.The muscles with longer duration of discharge were semitendinosus,erector spinalis and biceps femoris.The muscles with higher emg value and contribution rate are rectus abdominis,posterior deltoid and rectus femoris.During the take-off buffer period,the body muscles do work for the purpose of storing potential energy and maintaining body balance.2)jump stretching,forcibly order for bottom-up,triceps,rectus,glutes and strands of rectus muscle under the active control of central nervous system,the phenomenon of the"activate"beforehand,lower limb muscle activation sequence is glutes-strands of rectus muscle-calf,characterized by large joints drive the small joints of sports biomechanics;The upper limb muscle group discharged earlier,the gluteus maximus was inactivated earlier than rectus femoris,and the angular velocity of hip extension was faster than that of knee extension.The continuous discharge time of rectus femoris,gluteus maximus and spine erector was longer than that of gastrocnalis.The total contribution rate was 44.81%.3)during the suspension,deltoid toe,the upper trapezius muscle,monstrous,the biceps femoris muscle and the latissimus dorsi muscle performance for high integral electric value and contribution,make this a few muscles in the body to maintain the air stable position plays a large role,monstrous,the biceps femoris muscle strong contraction in addition to the stable center of gravity,but also to fly down legs folded forward form advantageous position;In the descending period,in order to make the spine flexion to the best Angle as far as possible,the rectus abdominis and external oblique do intense centripetal contraction,the emg value and contribution rate are high,the rectus femoris also shows a strong discharge level,and the knee joint actively extends forward to increase the landing distance.4)In the landing stage,the anterior deltoid,posterior deltoid and rectus femoris muscles discharge in advance.In order to avoid joint injury caused by rapid flexion of knee joint during landing,rectus femoris plays a key role as an antagonist to actively assist the landing of knees.At this stage,all muscles are highly coordinated in power generation,and there is no phenomenon that the discontinuous time of power chain is too long.The muscles with long discharge time are anterior deltoid and rectus femoris,which mainly assist the body to complete the landing safely and smoothly.The higher emg value and contribution rate are the deltoid anterior band and semitendinosus,which show strong contraction as the prime muscle.