Abstract

Three-dimensional high-speed cinematography was used to record the penalty throw in water polo by six elite male and six elite female players. The direct linear transformation technique was used in the 3-D space reconstruction from 2-D images recorded via laterally placed phase-locked cameras operating at 200 Hz. Five of the twelve subjects lifted the ball from underneath at the start of the throw whilst the remaining subjects opted for a rotation lift. As the ball was brought behind the head the females used very little hip and shoulder rotation compared to the male players so that four of the six female subjects were square on to the target at the rear point. At the completion of the backswing the wrist was flexed to a similar angle the elbow angle showed significantly greater flexion for females than males. During the forward swing, from rear point to release, the wrist joint of the female players flexed from a rear point angle of 158 deg to 148 deg at release. The wrist movement for male subjects was different from the females in that it flexed from 162 deg to 147 deg, 0.10 s prior to release and then extended to 159 deg at palmar release before again flexing to 156 deg at release. The amount of elbow extension during the forward swing was 48 deg for both groups; however, the females actually released the ball with the forearm vertical (89 deg) compared to the male forearm angle of 78 deg. Maximum angular velocity of the wrist and elbow occurred at release for 9 of the 12 subjects. Verf.-Referat (gekuerzt)