The Kinematics Analysis of Wu Yibing's Tennis Forehand Technique

Abstract

Objective: Search for the forehand swing stroke technical characteristics and kinematics rules of the outstanding young men's tennis players in the world. It provides some theoretical basis of Tennis forehand technique for tennis coaches and athletes. Research object: The world's elite teenage male tennis player Wu Yibing. Research methods: Using two JVC GC-PX10AC high-speed cameras (50 frames per second), the scene of the 2017 international tennis federation youth masters competition was filmed in the field. And the video recorded in the field was analyzed with a 3-D Signal TEC V2.0C software. Conclusions: (A) In the stage of the backswing: Wu Yibing's shoulder and hip angle has been obviously reversed. He uses his elbow to guide the tennis racket to lead the whole movement smoothly and form an “arcâ€. Wu Yibing's right wrist, elbow and shoulder keep a certain linear velocity, increasing the racket acceleration time and space. And the process of the traditional forward swing acceleration is extended to the backward stage.(B)In the stage of hitting the ball: Wu Yibing's shoulder and hip angle has been obviously reversed. To gain more control to counteract the impact of the ball, his right shoulder joint remains a small angle to reduce the radius. In tennis racket contact ball moment, the right shoulder joint and right hip joint linear velocity were 0.94m/s and 1.06m/s respectively. The right wrist and elbow joint linear velocity achieve a high standard of 11.81m/s and 5.56m/s respectively. (C)In the stage of the follow up: Wu Yibing's body center of gravity is not moving forward and the body's center of gravity is slightly undulating. However, his body's moving to the left is obvious. His right shoulder angle changes a little and the elbow lifts a little, but the right elbow is in the substantial rotation around the torso to the left. To increase the friction of the racket to the ball, there is a reacceleration of Wu Yibing's right elbow after the racket touches the ball. And his right elbow is rapidly spinning with a twist of the wrist. So he can play a powerful upper spin ball.