INFLUENCE OF LOWER EXTREMITY JOINT MOTIONS ON THE EFFECTIVENESS OF THE KICK IN BREASTSTROKE SWIMMING

Abstract

The study investigated how characteristics of an effective whip kick were influenced by movements of the feet relative to the hip and by the lower-extremity joint angles during the whip kick execution. Breaststroke swimmers of different skill levels were videotaped performing whip kick sprints. The obtained three-dimensional coordinates of selected body landmarks were used to determine the lower extremity joint angles and other pertinent characteristics of the whip kick. The results indicate that an effective downsweep is characterized by a small hip abduction angle, a negligible external hip rotation, partial hip extension, and increasing internal knee rotation. An effective insweep is characterized by negligible hip rotation, and ankle plantarflexion and inversion that were fine-tuned to the orientation of the other joints and the overall movement velocity.