Abstract

Highly skilled swimming is characterized by an extraordinarily high frequency of events. Within a second in time the swimmers must solve the difficult task of coordinating the motions of their body segments, for example, when swimming the crawl: (a) the pull-push phase of the right arm with the pull-push phase of the left arm; (b) the rolling motions pivoting on the longitudinal axis with the pull-push phase, the recovery phase, and breathing; (c) arm strokes with leg kicks; and (d) head movements when the swimmer inhales and exhales. Moreover, during different movements (e.g. during a pull-push phase), the geometric and dynamic movement pattern changes continually. The high frequency of events and the dynamic and geometric variations make subjective evaluation difficult even for the most observing and experienced coach, unless he or she has a method for obtaining objective data to support subjective conclusions. These data are achievable by quantitative measuring and scanning consistent with a theory-based conceptional model. In this way, the motions can be evaluated both qualitatively and quantitatively. The procedures described in this article enable one to ascertain the rate and the amount of the minima and maxima during each stroke cycle as well as the corresponding times at which each minimum and maximum occurred on the velocity-time and pressure-time curves. Thus, norms for an objective evaluation of swimming motions corresponding to the level of skills can be developed. Verf.-Referat