Remember not being in shape for a tennis match is no excuse for a loss.
Rod and Roy's favorite exercise was the double knee jump. This is an outstanding plyometric workout that will greatly improve your explosion on the court and cardiovascular endurance. This is an extreme move and is featured in both the P90X and Insanity workouts. If you are fit enough to attempt them you can expect to see large physical gains on and off the tennis court.
Be very careful when attempting double knee jumps, this move can be dangerous. The good news is there are modified moves that are safer but you can still achieve tremendous physical benefits.
The Jack Knife or more commonly known jumping jack is an exercise that is way underrated and used by tennis players. This move is particularly beneficial when warming up for a match because you activate all muscle groups from head to toe. The result is you will hit the court energized, seeing and moving to the ball early.