Three dimensional analysis of in-line skate turn using direct linear transformation method

Abstract

    The purpose of this study was to determine the characteristic of in-line skate turn by means of three dimensional analysis in 3 male college skiers. Subjects performed parallel turns during in-line skating on asphalt slope. One of the turns was videotaped by two cameras from two direction. Three dimensional coordinates of reference points on body, in-line skate and center of gravity of whole body (C.G.) was calculated using direct liner transformation method. The change of hip and knee joint angle, and the trajectory of C.G. during in-line skate turn were similar to those during ski turn characterized previously in literature. The change of ankle joint angle during in-line skating was larger than that during skiing. Trajectory of in-line skate during turn was not maintained in parallel. These data indicate that there are affinities of turn motion between in-line skate and ski, and suggest that in-line skate may be available for ski training.