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This biomechanic analysis focuses on the first serve technique in tennis, emphasizing the importance of pre-tension and arm positioning. The study reveals that releasing the pretension created by the tossing arm too early diminishes energy storage for acceleration. Key improvements suggested include maintaining the left arm's upward position until the forward hitting begins and increasing the distance between the hand and body for effective acceleration. Furthermore, enhancing wrist motion during the follow-through could significantly boost ball speed and overall performance.
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Sample Biomechanic Analysis First Serve
The body pretension, created by the high tossing arm is released too early by lowering the left arm; she still tries to keep tension, but she would have a better pre-tension if the left arm would remain up until the start of the forward hitting motion. Pre-tension is stored energy supporting the acceleration of the hitting arm. See frames 15, 16, 17 • To improve, the tossing arm should remain in the upwards position until the start of the upwards- forward hitting motion 16
The hand position and the elbow position at the start of the forward hitting motion are too close to the body; that shortens the acceleration distance to the contact point, resulting in restricted movement (see elbow position) and subsequently in lower racket head speed (see slide 19 yellow vertical line = start and green vertical line (slide 24) is contact point; the distance between these lines also includes the body transfer forward and is too short) • To improve, she should allow the racket head to continue its way down (after frame 15) without moving the elbow and the racket grip closer to the body to increase the acceleration distance to the contact point 18
The follow through could be more accelerated by more active wrist motion. In frame 26 we can see that the racket head has not fully overtaken the hitting hand. It should already be in the position indicated. • To improve, the active wrist motion through the contact point should be increased. Ball acceleration using this active wrist motion will increase in relation to lower arm strength gains. 26