title: Mechanical parameters as predictors of performance in alpine World Cup slalom racing.
abstract: The aims of the present study were to develop a method for classifying slalom skiing performance and to examine differences in mechanical parameters. Eighteen elite skiers were recorded with three-dimensional kinematical measurements and thereafter divided into a higher (HP) and lower performance group, using the ratio between the difference in mechanical energy divided by the mass of the skier and section entrance velocity (Δe(mech)/v(in)). Moreover, the skiers' velocity (v), acceleration (a), center of mass turn radii (R(CM)) and skis' turn radii (R(AMS)), ground reaction forces (GRF) and differential specific mechanical energy [diff(e(mech))] were calculated. v and diff(e(mech)) were different between the performance groups (P<0.001 and <0.05), while no inter-group differences in R(CM), R(AMS), a and GRF were observed. A relationship between R(AMS) and diff(e(mech)) was demonstrated (r=0.58; P<0.001). The highest GRFs were related to the lowest diff(e(mech)) and a was related to GRF (r=-0.60; P<0.001). The Δe(mech)/v(in) predicted the performance over short course sections. The HP skiers skied with a higher v and a similar range of diff(e(mech)). We suggest that shortest R(AMS) and the highest GRFs should be reduced in elite slalom in order to increase performance.
authors.affiliation: Department of Biomechanics, Faculty of Sport, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: M
authors.initials: M
authors.lastname: Supej
authors.forename: R
authors.initials: R
authors.lastname: Kipp
authors.forename: H-C
authors.initials: HC
authors.lastname: Holmberg
mesh_terms: D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D006801:Humans; D008297:Male; D055595:Mechanical Phenomena; D012865:Skiing / Q000502:physiology*; D017524:Slovenia; D014743:Videotape Recording