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  • Treat Your Knees to Elite-Level Tennis

    by Guest Blogger | Aug 08, 2016

    By: Angela Smith, M.D., FACSM

    From August 5 through August 22, the ACSM Sports Performance Blog is featuring a special content series in celebration of the achievements of elite athletes participating in international competition. Be sure to follow the blog as well as Facebook, Twitter and Instagram (acsm1954) and share using #ScienceofSport.

    Torn anterior cruciate ligament. Kneecap pain. Dislocated kneecap. Can you avoid them? Maybe – if you move like one of the elite tennis players competing this week!

    Torn anterior cruciate ligament (ACL) ends far too many sports careers. But tennis players almost never tear their ACL's, according to Dr. Alexis Colvin, chief medical officer of the United States Tennis Association. In my experience as a pediatric orthopedic sports medicine specialist, it’s almost unheard of for a young player to suffer a torn ACL or dislocated kneecap from tennis.

    When you stand on both feet, feet hip width apart, and bend your knees, are your knees as far apart from each other as your feet are? Bending your knees may push them a bit forward of your toes, but the middle of the kneecap should be in line with the second or third toe. As you step sideways in your partially squatting position, do the knees stay aligned over the toes, or do they turn inward? Your knees should stay just as far apart as your feet – knees over toes!

    The best tennis players, like the ones competing this week, learn great strategies for getting from corner to corner on the court, to manage to return a ball that looks almost impossible!  At the net, waiting for a ball in the ready position, the athlete has knees over toes, balancing on the front of the feet, often on the balls of the feet. He is ready to move quickly, at the last moment if needed, to reach a ball on the other side of the court. By the time he lands, his body weight is usually over the landing foot, with the knee well aligned between the body and the foot, not rotated inward.

    The elite tennis player runs, turns, pivots and cuts with her weight squarely over the foot, on the ball of the foot rather than flat-footed. She avoids landing with the flat-footed, heavy, off-balance, straight or hyperextended knee pattern that causes so many ACL tears. She lands firmly but with great shock absorption, well aligned.

    Land with toes and ball of the foot first, shock-absorbing knee bend, knees over toes. Whether your sport keeps you moving around a court, field, rink, or mat, move like an elite tennis player. Your knees may thank you!


    Angela Smith, M.D., is a Past President of the American College of Sports Medicine, specializing in pediatric orthopedics and sports medicine at Nemours/AI DuPont Hospital for Children in Wilmington, and practicing in  Bryn Mawr, Pennsylvania.

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