title: Key parameters of the swimming start and their relationship to start performance.
abstract: The swimming start is typically broken into three sub-phases; on-block, flight, and underwater phases. While overall start performance is highly important to elite swimming, the contribution of each phase and important technical components within each phase, particularly with the new kick-start technique, has not been established. The aim of this study was to identify technical factors associated with overall start performance, with a particular focus on the underwater phase. A number of parameters were calculated from 52 starts performed by elite freestyle and butterfly swimmers. These parameters were split into above-water and underwater groupings, before factor analysis was used to reduce parameter numbers for multiple regression. For the above-water phases, 81% of variance in start performance was accounted for by take-off horizontal velocity. For the underwater water phase, 96% of variance was accounted for with time underwater in descent, time underwater in ascent and time to 10 m. Therefore, developing greater take-off horizontal velocity and focussing on the underwater phase by finding the ideal trajectory will lead to improved start performance.
authors.affiliation: a Aquatic Testing, Training and Research Unit , Australian Institute of Sport , Canberra , Australia.
authors.forename: Elaine
authors.initials: E
authors.lastname: Tor
authors.forename: David L
authors.initials: DL
authors.lastname: Pease
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Ball
mesh_terms: D054874:Athletic Performance / Q000502:physiology*; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D013550:Swimming / Q000502:physiology*; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: biomechanics; dive; elite; kick-start; underwater