» Dislocated Shoulder
When paddlers panic, they usually start throwing their hands over their head and reaching out for as much water as possible with their paddle to prevent themselves from rolling over. It's at this point that the torque of pounding water on a paddle coupled with a hyperextended arm can pop the upper arm out of the shoulder socket. "Over 25 years, I've seen this injury scenario more than any other by a magnitude of ten," says Chris Hipgrave, director of Olympic programs for USA Canoe and Kayak. In addition to paddlers, climbers and martial artists regularly risk hearing the dreaded pop of a shoulder gone AWOL.

TREATMENT: "Assuming you don't need surgery for torn ligaments, you'll be in a sling for three weeks and definitely not back in a boat for at least two months," says Stephen Gunther, team physician for the U.S. kayak squad. After the sling comes off, "you've got to strengthen and tighten the rotator-cuff muscles to hold your shoulder in its socket and prevent additional dislocations," he says. Get the job done with shoulder rotations. Stand perpendicular to a closed door, right shoulder closest to the doorknob. Wrap a bungee cord around the knob and hold it with your left hand. Keeping your left elbow bent 90 degrees, tucked into your side, and your forearm parallel to the ground, sweep the cord from right to left as far as possible. Then face the opposite direction, grab the cord with your left hand again, and sweep it from left to right. Switch arms to strengthen your other shoulder. Start with one set of 15 reps and work up to five sets.

PREVENTION: "When things start going bad," says Hipgrave, "think about keeping your elbows tucked in and extending your torso as you reach out."