NEW YORK-It's not a bruising, contact sport like football or hockey - you only make contact with the water-but swimming is not an entirely injury-free activity. You've heard of the major league pitcher with the million-dollar arm who is sidelined by the dreaded rotator cuff injury. Swimmers can develop that, too.
   That major league pitcher at Wrigley Field in Chicago or the tennis player at the U.S. Open in New York might perform 1,000 repetitive arm revolutions in a week, but the competitive swimmer might go through as many as 16,000 arm revolutions in a week. In fact, Robert Gotlin, director of orthopedic and sports rehabilitation at Beth Israel Hospital in New York, told The Medical Herald that "an average 7- or 8year-old competitive swimmer does some 4 or 5 millions strokes at that young age.
    That kind of repetitive strain on the rotator cuff on the clavicular joint or the shoulder area in general just wears out the engine. The repetitive motion in the cuff muscles from the strokes of swimming is just an enormous load." So while swimming isn't a contact sport directly, it is indirectly in that the swimmer butts heads, so to speak, with a force. "The repetitive motion and the resistance of the water is not like the natural environment," ,said Gotlin. "You to into the water, and your groundstrokes meet the resistance of the water."
    It's the shoulder that overcomes that resistance and gets the strain, and it's the shoulder that's the Achilles Heel for swimmers, if one may mix a metaphor and a tendon or two. That tendon in the shoulder, when overused by constant arm revolutions, can get inflamed and you have tendonitis. Baseball, tennis and swimming are the sports with a high incidence of overuse injuries of the shoulder. Tennis and swimming are popular exercise activities for a great many fitness-conscious Americans in all age brackets and for both men and women.

Flexible, But Overtaxed

   In swimming, you repeat the same arm motion over and over with the shoulders, and this constant repetition can place very high demands on the structure, of the shoulders, that may eventually result in symptoms that put the swimmer in dry-dock.
    The shoulder is so flexible that it allows the arm to perform a complete circular revolution. It is loose, in other words. The problems develop with it becomes too tight or so loose that it is unstable.
    "The shoulder joint is one of the most mobile joints in the body," explained Jeffrey E. Rosen, M.D., assistant professor of Clinical Orthopedics at New York University Medical Center and Director of Child Analysis-Sports Medicine, "and as a result of that you gain mobility but you sacrifice stability.
    "It allows us almost a universal motion of the arm to be placed in a full circle, which allows you to do freestyle and backstroke and a full overhead range of motion. However, in order to gain that ability the shoulder is an inherently unstable joint in the body.
    "One of the most common problems that we see in young athletic swimmers is that they suffer from shoulder problems," he said. "Many swimmers from repetitive overhead activity swimming motions develop shoulder pain and shoulder laxity that needs to be managed with aggressive physical therapy programs and in rare cases surgery.
   He didn't mean to suggest, however, that swimming isn't a good exercise. "Swimming is excellent, you know. As a means of fitness, swimming has excellent benefits. Basically, it's a nonimpact activity. There's less stress on the lower extremities, like the knees and the ankles, and it provides an excellent way of obtaining cardiovascular fitness. Swimming as it relates to the heart is an excellent cardiovascular workout.
    "It provides an excellent muscle workout because it really involves all the muscles in the body in a way that no other activity really can."The problems usually result from overuse and stretching out of shoulder ligaments, he said. "That can be counteracted with a good physical therapy program, whereas many of the contact sports result in traumatic type injuries to the shoulder and are more often going to lead to surgical treatment.
    "People who do get injured really need to be in supervised physical therapy programs with people who really know how to rehabilitate shoulders.
    What kind of injuries require more advanced treatment? "When a swimmer's shoulders become too lax they are not able to work their way back to competition or activity because they've become too loose," he said.
    "They overstrain their rotator cuff muscles to the point where they just can't seem to get back. Patients who fail an extended physical therapy program for six months may end up needing surgical stabilization in order to get back to the ability to rehabilitate the shoulder and progress to activity.
    "The shoulders in elite swimmers tend to be kind of loose," agreed Jonathan L. Chang, M.D., Clinical Assistant Professor at the University of Southern California. "There's a certain advantage to that. But there is a drawback too, because if it's looser it means that there is more instability associated with it.
    "If you have what we call excessive shoulder laxity you can improve on that by doing what is known as the thermal capsular shrinkage. It uses radio-frequency energy either as a cartery unit or as a laser unit.
    "We don't think it matters which unit you use provided it ends up with the same results because what you're looking to do is heat the tissue to a certain temperature. It helps to degrade the collagen to the point where it shrinks the capsule. That's one of the newer things being utilized for this purpose."
    Most first-time injuries are usually not major problems, he said. If ordinary treatment doesn't work, then "it would probably be a good idea, if they are a competitive swimmer, to refer them to a sports medicine orthopedist for a more thorough evaluation. Because shoulder problems can be very difficult to diagnose."

Not Weight-Bearing

   Generally, said Chang, he recommends swimming because it is "clearly going to be beneficial to a patient.
    "Swimming is good as a cross training method. It uses different muscles and even the same muscles differently than you would on land. But there are some clear limitations to this because it is not a weight-bearing exercise. Part of the concern, particularly for women, is trying to stay fit and keep their bone density good. Unfortunately, swimming does not allow you to get that. From the standpoint of trying to maintain bone density to prevent osteoporosis, swimming is not a good way to do that."
    Gotlin of Beth Israel noted that if a shoulder shows some calcification or calcific tendonitis or some overuse tendonitis, "the new electro-shock wave therapy they're using for the heels and the ankles also would be applicable to the shoulder as well, if indeed it is going to work.
    "This is all new and we don't have five-year data, but electro-shock wave therapy or the high frequency lipotripsy new stuff they are using for the ankles would also be applicable to the shoulder as well for those with calcification or calcific tendonitis.
    "This is basically shoulder pain and when an x-ray is taken an actual area of calcium is seen on the x-ray. It's something that those of us in the field are going to be evaluating over the next year or two."
    Heidi Heilman, Physical Therapist and Site Coordinator for HealthSouth in Austin, Tex., says that most swimming strokes are "shoulder driven.
    "To propel through the water, the arms are used much more than the legs. People rarely kick. The kick is the weakest part of their strokes. So their shoulders tend to get overworked.
    "A lot of the time the injuries result from an imbalance between the muscles. With the breaststroke kick, they'll work the inside muscles a lot more than the outside muscles and so they'll end up with imbalances around the knee.
    "Same thing with the shoulder. They'll use the muscles on the anterior side of the shoulder versus the posterior ones and because of that imbalance the shoulder becomes less stable and then they would get the repetitive overuse injuries."
    She stressed the need for cross-training, not concentrating solely on swimming, "With any sport, cross-training is so important. A lot of recreational swimmers or weekend swimmers are so focused about getting their swimming workout in that they don't realize they need to work out in the gym, or do some other kind of cross training.
    "High-school athletes, college athletes, Olympic athletes, they all cross train and get in the gym and work muscles that they don't necessarily use with swimming just to keep their body balanced out.
    "Once swimmers want to get into competitive swimming. they only have time to swim and they forget about all of the rest of the training they need to stay balanced and prevent injuries.