Your knees take a pounding on a tennis court.  Here's how to keep them in working order.

By Dana Sullivan

As tennis has evolved, so have tennis-related injuries. Take the knees. “Now that most players hit with an open stance, traumatic injuries to the knees, such as torn ligaments, are pretty rare,” says Dr. Jon Schriner, D.O., medical director of the Michigan Center for Athletic Medicine in Flushing, Mich. The open stance helps protect your knees because there’s less rotation over the knee than with the closed stance. But still, overuse injuries plague almost every player at some point, and knees are near the top of the list. Part of the problem is that playing too much of one sport leads to muscular imbalances. Your quads are strong from the running you do on court, but unless you’re diligent about strengthening your hamstrings, those weaker muscles can’t counter the forces put on the knees with every lunge and quick start or stop. “Developing equal strength between the opposing muscles that support the knees is essential,” says Timothy E. Hewett, Ph.D., director of the Sports Medicine Biodynamics Center at the University of Cincinnati College of Medicine. “But you also want each leg to be equally strong, stable, and flexible.” Another cause of knee pain can be tight iliotibial bands. IT bands are ropes of fibrous tissue and muscle that run from the hips to the tops of the tibia bones. “If these bands are tight, they can force the knee caps to pull laterally, causing friction that can wear down the cartilage in your knees,” Hewett says. For optimal knee health, he recommends singleleg exercises such as squats and lunges, plus the exercises described below. If your knees are already aching, take at least a week off from tennis and use “R.I.C.E.” therapy, says Schriner. That is, Rest and Ice your knees, use Compression, and Elevate them as much as possible. If you go back to tennis and the pain returns, there’s obvious swelling or redness, or if you hear clicking or popping, see your physician.

Bracing Your Knees

The following exercises will strengthen your hamstrings and quads, the major muscles that support your knees. Do the first three moves at least twice a week (always with a full day of rest in between); do the side bends every day. Proper form is essential, so if the suggested repetitions are too challenging, do as many as you can with good form and work up from there.

1. BOUNDING This exercise is basically skipping, but you do it slowly and with exaggerated movements. If possible, do this on a soft surface, such as grass. Stand with one foot slightly ahead of the other, arms at your sides. Push off with the back leg, driving your front knee forward and upward to gain as much height and distance as possible. Land softly. Repeat with the opposite leg and continue alternating to complete 30 bounds. Rest for 30 seconds and repeat twice more.

2. SINGLE LEG BALANCE Stand on a BOSU Balance Trainer (available at bosu.com) in the ready position with your feet shoulder-width apart and your knees bent. Lift your left foot a few inches and slowly lower your body into a one-legged squat by bending your right knee and leaning forward from the hips. Look forward, and keep your back straight and your abdomen tight. When your right knee is over your toes, use your glutes and hamstrings to push back up to the starting position. Repeat 8–10 times. Switch legs and repeat. Complete three sets. For more of a challenge, hold a 3–5-pound dumbbell in each hand.

3. RUSSIAN HAMSTRING CURLS Kneel on the floor and have a partner hold down your ankles. Cross your hands in front of your chest. Tighten your abdominal muscles and slowly lower your upper body forward from your waist, keeping your back straight. Your partner should hold your ankles firmly in place so your feet don’t come off the ground. Lower until your upper body is at a 45-degree angle from the floor. Lift yourself back to the starting position and repeat five times; increase to eight repetitions as you get stronger. (If you can’t pull yourself back up, gently fall forward, catching your body with your hands in the push-up position.) Rest 30 seconds and repeat twice more.

4. SIDE BENDS Stand with your feet wide, arms out to the sides. Bend to the left from the waist until you feel the inside of your left thigh stretch. Hold for at least 30 seconds. Repeat in the opposite direction. Complete three stretches on each side.