Sports Biomechanics Analysis On The Technique Of Inside And Outside Instep Set-Pieces Kicking Of Female Football Elites In Shaanxi Province

The Objectives and methods: Football is a worldwide sport with integrity,antagonism,variability,ornamental value etc.This paper mainly focuses on the technique of inside and outside instep set-pieces kicking,using two high-speed cameras,telemetry electromyography and three-dimensional force platform to test synchronously.In the experiment,the female football elites of different levels in Shaanxi Province were selected as the test object,including two national master athletes,two national first-class athletes and two national second-class athletes.In order to scientifically and intuitively obtain the kinematics,dynamics and surface electromyography of the related technical movements through the experimental data,the experiment refers to the multi-disciplinary contents such as athletic training,movement anatomy,exercise physiology etc as the theoretical basis,and objectively reflects the parameter indexes of the technique on inside and outside instep set-pieces kicking.This paper summarizes the common and individual relationship between the two techniques,and provides a reference for the sports biomechanics parameters and technical diagnosis of female football training and football teaching in the future.Results: Through the experimental analysis,this study divided the technique on inside and outside instep set-pieces kicking into four stages: kicking leg active back swing stage,thigh front swing stage,crus front swing stage and ball kicking stage.The results show that:Firstly,in the stage of active back swing,the inside instep kicking of six female football players in Shaanxi Province is longer than the outside,and the angle of the swing leg is different.The angle of hip joint of kicking leg on the inside instep kicking is larger than outside.The range of the swing leg is related to flexibility of the joint angles,the larger angle of hip joint,the greater more space of back swing.In the stage of active back swing,athletes should focus on the strength training of the right rectus femoris muscle,the anterior tibial muscle and the gastrocnemius muscle.Secondly,in the stage of thigh front swing,there was no significant difference in the swing time of inside and outside instep kicking for the six female football players.All the other five athletes showed characteristic of forward swing except Zou: the shank flexion backward toward the hip in order to crate the advantage conditions for the shank swing forward at a high speed.And the EMG showed that the right erector spinae,the rectus femoris,the biceps femoris and the tibialis anterior muscle had discharge intensively,and the discharge of biecps femoris was the most obvious in the inside instep kicking.During the inside and outside instep kicking,the supporting leg stand the largest force in the vertical direction(Fz)when stepping on the force measuring platform.Thirdly,in the stage of crus front swing,the thigh front swing of inside and outside instep kicking of six female football players in shaanxi Province spent more time than the crus front swing.In the inside instep kicking,all the other five athletes except Zou showed the movement characteristics of long thigh forward swing time and short crus forward swing time.The EMG showed that all the six athletes discharged in right biceps femoris muscle,gastrocnemius muscle and left tibialis anterior muscle.In the stage of crus front swing,the football players should not only focus on the strength training of lower limbs muscles,but also on the balance and stability of the supporting leg.Finally,at the moment of ball kicking,there are some differences in the length of time among the six female football players,which is closely related to the other stages swing time and the range of swing leg.However,the muscle strength of those six athletes was basically the same,so it shows that the right rectus femoris and the anterior tibial muscle had a strong discharge phenomenon,and the strength of the four muscles supporting leg is obvious.