ABSTRACT
The International Tennis Federation (ITF) has officially amended the Rules of Tennis in order to approve the use of two new types of balls in tournament play. The aim of introducing the new balls is to increase the speed of the game (fast-speed, Type 1 ball), or decrease the speed of the game (slow-speed, Type 3 ball), compared to the speed of the game when using the regular (medium-speed, Type 2) ball. The Type 1 ball is the same size as the Type 2 ball, but is harder and has a lower coefficient of restitution (i.e., bounces less), thereby allowing for a lower rebound angle after contacting the court surface (Blackwell and Heath, 1997). This ball is meant for play on a slow pace (Category 1) court surface (e.g., clay). The Type 3 ball has the same bounce and mass as the Type 2 ball, but is 6% larger in diameter. The larger size of the Type 3 ball allows for a greater amount of drag due to air resistance as well as a greater Magnus effect (i.e., the ball’s path tends to curve more due to the ball’s rotation), when compared to the Type 2 ball. The Type 3 ball, therefore, moves through the air more slowly, has a shorter horizontal distance through the air, and topspin tends to allow the ball to clear the net and still land in the court boundary more easily than the Type 2 ball (Blackwell and Heath, 1997). The Type 3 ball is meant for play on a fast pace (Category 3) court surface (e.g., grass), and was the focus of this study.
