A proper swing (racquetball swinging tips) is key to preventing injury to yourself when playing racquetball. It doesn’t have to be picturesque but it should have the major components in place. Your swing is really all about managing the movement of the body. The key areas are the legs, clearing the hips for the swing, square shoulders, getting the arm back, and cocking the wrist for snap. (From racquetball swinging tips)
Areas of concern:
Keeping shoulders closed. Causes stress on rotator cuff. Head should rotate from front shoulder and finish closer to other shoulder. This means that you rotated your upper body with the shot.
Your front foot should step in the direction you are trying to hit the ball, if possible. If you try to hit a ball without having your foot properly aligned then all of the torque goes into your front knee. You can try to hit a ball on one side of the court to the other side (cross court passing shot) but keep your body facing the side wall. Do this very very slowly and carefully. You will feel the stress on your knee. Your knees are not built to withstand torque from the side. Therefore, your front foot should be pointed towards your shot.
• Calves and heel,
Lower leg injuries usually occur because of landing on your heel instead of the balls of your feet. You will hurt your heel, achilles, ankle and calf if you constantly stop yourself with your heel instead of the balls of your feet. It is like a baseball player that stretches for first base and hits the bag with his heel. There are a lot of bad things that can happen.
Not rotating properly on swings puts undue torque on your back. If you are not rotating (head from front shoulder to back shoulder.) then you are putting torque on the muscle in your upper back. (This is usually a faulty follow though (backswing)) You maybe hitting the ball and stopping your swing at contact. You should be rotating your shoulders and hips fully before you stop your swing.