Wear Eye Protection
A racquetball travels at 85-110 mph and the racquet can move at 85-90 mph. If either one catches you in the eye, the pain will be intense and permanent injury is a definite possibility. So be smart and wear eye protection, preferably industrial-strength, shatter-proof lenses that feel comfortable and allow maximum vision.

Don't Skimp on the Warm-Up
Racquetball is a fast-action game with lots of starts and stops, twists and turns. Your risk of injury is off the chart if your entire body isn't warmed up and ready. So take a few minutes to stretch out before (and after) you play, and be sure to move your arms and shoulders through their entire range of motion. Wrap up the warm-up with some easy forehands, backhands, ceiling shots and a few shots off the back and side walls, just to get your rhythm going and your mind in gear.

Check Your Body Stance
Racquetball is such an easy game to grasp that some people never bother to learn the basics of body position. Indeed, a poor body stance is one of the most common mistakes you can make, causing your shots to be weak and inaccurate. To improve, make sure your body faces the side wall as you swing, not the front wall. A right-handed player should have toes pointing to the right wall on the forehand, to the left wall for the backhand. And don't hit from a too-erect body position. Instead, bend your knees and lower your base of support, keeping feet apart. A low, springy stance gives you more power and agility.

It's All in the Wrist
Strong, snappy wrist action can add a lot of power to your game. So do a little off-court conditioning. Push-ups, especially fingertip push-ups, work your wrists and so do pull-ups. Strengthen your wrist extensors and flexors by exercising with a 3- to 10-pound dumbbell, slowly curling up and down from the wrist. Gradually work up to three sets of 10 repetitions with the palm side down, and the same with the palm side up.