A Biomechanics Analysis Of The Lower Limb Of Amateur Badminton Players During Chopping And Picking In Front Of The Net

Objective: with the rapid development of modern badminton,the number of people participating in the sport of badminton has increased.The vast majority of amateur badminton players lack correct training guidance,and the probability of injury is extremely high.Comparing badminton amateur players chopping and picking up the shuttlecock in the frontal of the net with two different techniques,analyzing the differences in kinematics and kinetics of lower limbs,including ankle,knee and hip.To understand the badminton net chop and pick the ball technology regularity and characteristics,then explore and find the relationships with sports injuries.Providing relevant prevention advice and training for majority of amateur badminton players to reduce the incidence of sports injuries.Methods: 15 subjects were required to be fit and healthy,with no upper or lower limb sports injuries within half a year.The badminton level of the subjects was required to be college students majoring in badminton,with a badminton playing age more than 5 years,and dominant side is right.The kinematics data were collected by Vicon 3D capture system,and the main joints angle of the lower limbs(ankle,knee and hip)were compared.Novel Pedar-X insole pressure measurement system and Kistler 3D force measuring platform were used to collect the kinetics data.The plantar data were analyzed with parameters of vertical ground reaction force(GRFs),peak pressure,maximum pressure and pressure-time integral.Paired sample T test was used for statistical analysis,and the significance level p was set as p ? 0.05.Results: In terms of kinematics,comparing to chopping,the range of motion(ROM)of the ankle,knee and hip was greater during picking.At the time of ‘c',subjects showed significant inversion and dorsiflexion during picking.Comparing to chopping,subjects exhibited greater knee abduction at the time of ‘b' and ‘c' when picking.In the horizontal plane,subjects represented significant hip internal rotation at the time of ‘a' and ‘c' during picking.In the terms of kinetics,comparing to picking,subjects showed much greater ground reaction force at the initial peak during chopping,there was no significant difference at the second peak between chopping and picking.Subjects showed much greater peak pressure in forefoot and rarefoot areas between chopping and picking.During the picking,the subjects showed more significant force-time integration in the middle and rearfoot area,especially the lateral heel and the lateral middle foot,while there was no significant difference in rearfoot between chopping and picking.Conclusions and implications: We found subjects showed greater ankle joint range of motion when picking.Long-term instability of the ankle joint would lead to chronic ankle joint injury.In addition,the subjects showed more significant knee abduction and hip internal rotation during picking,which would be related to knee joint injuries,including ACL injury and patellofemoral pain syndrome,which may be related to the passive body position.According to the relevant measurement data of the kinetics test,we found the time-pressure integral of the lateral heel and the lateral area of the middle foot was significantly greater during picking,which was more likely to cause the ankle inversion and the ankle sprain.When chopping,the peak pressure in the area of the other four toes was higher than picking,representing a more significant function of grasping the ground of foot.Subjects returned back was quicker when chopping comparing to picking,which was related to the active body position.For amateurs,it's worthy to explore a comprehensive training program with correct techniques,especially the foot landing posture with high risk of injury.Loading alleviation-related protection braces and athlete-specific badminton footwear for minimizing the ligament injury are quite essential.In addition,it is suggested to train the ability of toe to grasp the ground and the muscles around the ankle joint to strengthen the stability of the ankle joint to reduce the sports injury of the ankle joint.Amateur badminton players are suggested to arrange time reasonably and pay attention to the injury parts of themselves which are most likely.