Whitewater rafting on the Nantahala, Ocoee, Chattooga, Pigeon, French Broad, Nolichucky, Cheoah, New and Gauley Rivers with NOC

Imagine a basketball balanced on a golf tee. The basketball is the end of your humerus bone. The indented part of the tee the basketball is balancing on is your shoulder joint. It's not very deep, and it's not very big, considering the large ball that's resting on it. And therein lies the problem. The shoulder socket is very small, while the humerus bone resting on that socket isn't. The shoulder socket is designed for range of motion, and not designed to be a weight bearing joint (like how paddlers use it for bracing, turning, or rolling). In contrast, the hip socket is a weight bearing joint - the bone is set deep in the socket for stability and to prevent a large range of motion. (This explains why dislocating a hip is horribly painful)

The ratio of a basketball to a golf tee is actually pretty accurate when describing the shoulder joint. Now imagine how easy it is to knock that basketball off the tee and you can see why shoulder dislocations are fairly common. If not for the skin, muscles, tendons, and ligaments that surround the shoulder, humans would perpetually walk around in slings. As it stands though, it's only kayakers that perpetually walk around in slings. Usually, the paddle is the culprit when a kayaker dislocates his shoulder. Archimedes once said, "Give me a lever long enough and a fulcrum to place it on and I'll move the world". Your paddle is that lever, and although it's only 197 centimeters long, it's plenty long enough to apply the minimum pressure required to knock that basketball off the tee. Keeping your shoulder in a strong position while paddling is therefore of utmost importance. A strong position is one in which the elbows stay below the hands and the hands stay in front of the torso. The easiest way to achieve this strong position is by rotating your torso with all your strokes - especially strokes done at the back of the boat.

Below are two pictures of a sweep stroke. In the first, the paddler has rotated his upper body with the stroke. His elbows are bent and below his hands, while his hands are in front of his torso. This is a strong position. In the second picture a paddler has not rotated his torso when doing the sweep stroke. You can see that the elbow is above the hand, and the hand is not in front of the torso. This is a weak position.