Most tennis players rely on the ball's quick bounce to help them play and score. However, in the cold of winter, that ball might become your adversary. Tennis.com suggests stringing your racket 2 pounds lower during the winter months to compensate for the ball's diminishing bounce. 4 players, 1 tennis ball, and service boxes are required. Setup: This is a little variation on the traditional game of touch tennis. Within the service boxes, each player has their own box, and they are accountable for each ball that enters their box. Drop the ball on the net to begin the point out, and then play the point out. Place four tennis balls in the freezer, four in the fridge, four at room temperature, and four in the sun. If feasible, leave the tennis balls in situ for at least one to three hours. When you're ready, remove the balls one at a time and drop them from an elevated position. Have someone else measure and record the height of the ball's bounce.