A biomechanical analysis of the Olympic-style flatwater kayak stroke.
To investigate the biomechanics of flatwater kayaking, the technique of nine Olympic caliber K-1 paddlers was analyzed using cinematographic and computer procedures. Results indicated that, during paddle-water contact, the horizontal arm action was one of push-then-pull with the push coming from the arm farthest from the water (thrust segments) followed by the pull coming from the arm closest to the water (draw segments). During this action, the center of paddle rotation shifted up the paddle shaft as the stroke progressed, which increased the time the paddle was in the power phase of the stroke. The horizontal movement patterns of the individual segments indicated that the push was accomplished by an integrated movement of the thrust wrist and elbow, with minimal shoulder involvement. Subsequently, the pull was accomplished by an integrated movement of the draw wrist, elbow, shoulder, as well as the thrust shoulder. During the latter stages of water contact, since the performers were unable to generate additional useful power, the paddle was rapidly withdrawn to avoid dragging. Subject stability in the frontal plane was maintained by shifting the body mass toward the water contact side at paddle entry and away from it at exit. This action opposed the vertical forces produced as a by-product of the stroke. The final outcome of this stroke technique was the maintenance of the body center of gravity velocity while the boat oscillated under the performer.