A short blocking action is all that is required to take advantage of this energy. At the baseline, the bounce of the ball reduces incoming speed. A longer and faster swinging action is necessary to give the ball the zip needed. A firm grip is still required, but the speed and momentum of the swinging racquet enables you to win this collision. When serving, the ball during the toss has no significant speed and adds little to the power the serve.
Racquet speed is key.
The longest and loosest swing is best. In this instance, weakening the grip increases racquet speed. Although the best answer may be whatever feels comfortable, the diagram below provides a simple method of determing an appropriate measurement. Use it as a starting point. All rights reserved.