The Answer

‘Research into hitting skills has shown that the trunk and upper limbs rotate in hand based movements, while the trunk and lower limbs rotate in foot based movements’ (Zatsiorsky, p.491). The body position is important when performing a tennis serve, as it will allow us to produce sufficient forces which will maximise the speed of the ball, along with a topspin, and the swing back of the tennis racket to make the serve successful.

Force may produce motion and speed of the tennis ball, therefore we need to know where the best places are to apply force. In a tennis serve, these places are between the hand and the racket and most importantly between the racket and the ball when they make contact.

 
The physical dimensions of a tennis racket and ball is part of what influences the tennis serve, along with applying sufficient torque. A tennis racket with grater mass increases the joint torque throughout the serve, which allows for a straighter hit. Taking into consideration the coefficient of restitution, you would need to find a racket with the greatest mass that still allows high swing velocity. The length of the racket also influences the speed, with a longer racket increasing torque, which increases speed of the ball. This highlights the importance of a tennis racket as a lever and the importance of using it successfully to enhance the serve.