ACL Exercises

Eighty thousand Americans tear their ACL each year, according to "USA Today." The ACL, or anterior cruciate ligament, is the main stabilizing ligament in the knee. Exercises that improve balance, strength and range of motion in and around the knee both prevent ACL injuries and are part of a recovery program after an injury. If you have an injury, do not push yourself to the point of pain and speak with your doctor about an appropriate program.

Hamstring Strengthening

Hamstring strengthening exercises help you prevent or heal from an ACL injury because the thigh muscles stabilize the knee. The hamstrings connect your pelvis and the backs of your knees. Strengthening the hamstrings also helps you regain motion in the knee after an injury. The hamstrings bend the knee.

The hamstring curl is an exercise you can perform for stronger hamstrings. Lie on your abdomen with your arms crossed on the floor in front of your and both legs straight. Then, bend the injured knee as far as you can and do not lift your thigh off the floor.

Quadriceps Strengthening

Strengthening the quadriceps also improve knee stability and motion. The quadriceps run the length of the front of the thigh and connect at the knee. This muscle group straightens the knee joint.

An ACL exercise that strengthens the quads is the wall sit. The wall sit lets you perform a squat, but using a wall to support some of your weight and to help you maintain correct posture. To begin, place your back against a wall and your feet 12 to 24 inches from the wall with your legs straight. Then, bend your knees and slide your back down the wall until your quads are parallel to the floor. Maintain the position for 10 to 30 seconds.

Exercises that involve jumping also strengthen the quads, but these exercises are generally best for preventing ACL injuries, especially in athletes who can tear their ACL doing quick movements during sports.

Balance Exercises

Exercises that strengthen the knees also strengthen the ACL, but the ACL also helps you balance on one leg. Balance exercises such as the balance on one leg are therefore part of an ACL recovery program. To perform this exercise, balance standing only on your injured leg with your knee bent slightly for up to 15 to 30 seconds. Do not hold onto a chair or wall to assist you, but make sure one is nearby in case you need it.

Range of Motion Exercises

An ACL injury usually limits your range of motion in your injured knee. Range of motion exercises increase the flexibility and mobility of the knee joint. One of the most common range of motion ACL exercises is the heel slide. To perform the heel slide, lie on your back with your legs straight. Bend the knee of your injured knee and slide your heel along the floor as close to your buttocks as you can. Hold for five seconds and then slide the leg forward.