| Purpose: By applying the methods and means of sports biomechanics,this paper analyzes the contribution of lower limb muscle coordination,mechanical conduction and the change characteristics of human center of gravity during the movement of Wuxing Tongbei boxing,reveals the relationship between the stability of the center of gravity and the change of lower limb muscle coordination,and provides experimental evidence for the function of Wuxing Tongbei boxing to improve the dynamic stability of human body.It provides theoretical basis for the promotion of exercise methods and exercise methods for the prevention of falls.Methods: In this study,the fourth generation of Wuxing Tongbei boxing was taken as the test object.The movement biomechanical parameter changes were collected synchronously by Nokov motion capture system,AMTI force measuring platform and Biovision multi-guide motion bioelectrotelemetry recording and analysis system.The subjects completed 6 groups of five elements Tongbei boxing circular sky movements,and the data of 3 groups of movements were selected for analysis.The kinematic parameters of the subject’s hip,knee and ankle in sagittal plane,coronal plane and horizontal plane,center of mass(COM)and so on were obtained by the Seeker software contained in Nokov motion capture system.The dynamic parameters of the Center of Pressure(COP)in front,back,left and right directions and up and down directions were obtained by the AMTI force measuring platform.V3 d software was used for simulation modeling to obtain three-dimensional force parameters of each lower limb joint.Biological parameters such as IEMG,RMS,muscle contribution rate and coactivation index of knee and ankle muscles of eight muscles of lower limbs including gluteus maximus,rectus femoris,medialis femoris,lateralis femoris,biceps femoris,tibialis anterior,medialis and lateralis were obtained by Biovision multi-channel sports bioelectrical remote measurement recording and analysis system.Descriptive analysis was used to describe the circumferential movement characteristics of Wuxing Tongbei Boxing,and paired sample T test was used to compare and analyze the difference between the data of center of mass(COM)and Center of Pressure(COP)of human body during movement.origin software is used for drawing processing.The results are as follows:(1)the maximum rocking area of the human center of gravity of the lion ball is 0.37 m in the forward and backward direction,the maximum rocking area of the human center of gravity of the fish ball is 0.34 m in the left and right direction,and the maximum rocking amplitude of the center of gravity of the mountain and sea is 0.27 m in the left and right direction;The COP of the three actions was symmetrical,and the rolling area was between 0.01m—0.02 m.(2)The variation amplitude of torque of lion ball rolling,fish pose and mountain and sea rocking motion in sagittal plane,coronal plane and horizontal plane is hip joint >Knee joint >For the ankle joint,the difference of peak torque was the peak torque flexion extension of the hip joint >Internal and external rotation >Adductor abduction moment,peak adductor abduction moment of knee joint >Internal and external rotation >Peak flexion and extension moment,adduction and abduction of ankle joint >Dorsiflexion toe flexion >Peak torque of inside and outside turning.(3)In a single exercise cycle,the gluteus maximus and tibialis anterior contributed the most among the seven muscles,34.9% and 11.1%,respectively.The coactivation index of biceps femoris and rectus femoris in knee joint,(4)The activation index of all ankle muscles was the highest(97%).The contribution rates of femoris lateralis and tibialis anterior were the highest,which were 17% and 10%,respectively.The coactivation index of biceps femoris and rectus femoris was 87%,and that of tibialis anterior and sural lateral was 84%.The contribution rates of biceps femoris and lateral femoris were 18.03% and 18.87% respectively.The highest coactivation index of the tibialis anterior and sural lateral muscles was 93%.(5)In the first stage of lion ball rolling COG,the length of changing track is significantly correlated with knee joint muscle coactivation index and knee joint muscle coactivation index,and the length of changing track in the up and down direction is significantly correlated with knee joint muscle coactivation index.The trajectory length in the left and right directions had a strong negative correlation with the ankle muscle coactivation index(-0.97),and a strong positive correlation with the ankle muscle coactivation index(0.60).The trajectory length in the anteroposteric direction had a negative moderate correlation with the ankle muscle coactivation index(-0.39),and a weak correlation with the ankle muscle coactivation index(0.119).In the second stage,as in the first stage,COG movement distance in the left and right direction was negatively correlated with knee muscle coactivation index,and the correlation was-0.525 with moderate intensity.There was a positive correlation with the ankle muscle coactivation index,and a strong correlation was 0.935.In the anteroposterior direction,COG moving distance was negatively correlated with knee muscle coactivation index(-0.529).It was positively correlated with the ankle joint muscle coactivation index(0.577).COG moving distance was positively correlated with knee joint coactivation index,which was 0.459 with moderate intensity.(6)In the first stage of the COG COG,the length of the left and right,back and forth changing trajectory was significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index,and the correlations were 0.86 and-0.60 with knee joint muscle coactivation index and-0.74 and 0.66 with ankle muscle coactivation index,respectively.In the second stage,COG’s changing track length from left to right,back to back,up and down is significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index,and the correlations with knee joint muscle coactivation index are-0.96,0.96,-0.93,and ankle muscle coactivation index are-0.97,-0.88,respectively.0.94;In the third stage,COG’s change track length from left to right,before to after was significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index,showing a moderate intensity correlation basically.The correlations with knee joint muscle coactivation index were-0.43 and 0.391,and those with ankle joint muscle coactivation index were 0.263 and-0.579.(7)In the first stage of shaking the mountain and shaking the sea,the length of COG changing track from left to right and from front to back was significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index,and the length of the changing track in the up and down direction was significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index.The correlations with knee muscle coactivation index were-0.73,-0.56 and 0.24,respectively.The correlations with ankle muscle coactivation index were-0.81,-0.56 and 0.21,respectively.In the second stage,the length of COG’s changing trajectory from left to right,back to back and up and down was significantly correlated with knee joint muscle coactivation index and ankle joint muscle coactivation index.The correlations with coactivation index of knee muscle were-0.86,0.34and-0.71,respectively.Correlations with ankle muscle coactivation index were-0.90,0.25,and-0.77,respectively.Research conclusion: Zhoutian form through the lower limb hip,knee,ankle joint force to complete the movement,enhance the strength of the joint at the same time to improve the coordination of the plantaris pressure center of the rocking area in a small range,improve the ability to move the center of gravity,so as to improve the lower limb posture control ability,through practice can improve the human dynamic balance ability,further prevent the occurrence of falls,It can be promoted according to the needs of different groups. |
PDF Full Text Request