title: Kinematic Chains in Ski Jumping In-run Posture.
abstract: The concept of kinematic chains has been systematically applied to biological systems since the 1950s. The course of a ski jump can be characterized as a change between closed and open kinematic chains. The purpose of this study was to determine a relationship between adjacent segments within the ski jumper's body's kinematic chain during the in-run phase of the ski jump. The in-run positions of 267 elite male ski jumpers who participated in the FIS World Cup events in Innsbruck, Austria, between 1992 and 2001 were analyzed (656 jumps). Two-dimensional (2-D) kinematic data were collected from the bodies of the subjects. Relationships between adjacent segments of the kinematic chain in the ski jumper's body at the in-run position are greater nearer the chain's ground contact. The coefficient of determination between the ankle and knee joint angles is 0.67. Changes in the segments' positions in the kinematic chain of the ski jumper's body are stable during longitudinal assessment. Changes in shank and thigh positions, in the sense of increase or decrease, are the same.
authors: Institute of Physics, Faculty of Mining and Geology, Technical University of Ostrava, Czech Republic.
authors: Eva
authors: E
authors: Janurová
authors: Department of Natural Sciences in Kinanthropology, Faculty of Physical Culture, Palacky University, Olomouc, Czech Republic.
authors: Miroslav
authors: M
authors: Janura
authors: Department of Graduate Programs in Health Sciences, School of Graduate Medical Education, Seton Hall University, South Orange, New Jersey, U.S.A.
authors: Lee
authors: L
authors: Cabell
authors: Department of Natural Sciences in Kinanthropology, Faculty of Physical Culture, Palacky University, Olomouc, Czech Republic.
authors: Zdeněk
authors: Z
authors: Svoboda
authors: Department of Physiotherapy, Faculty of Physical Culture, Palacky University, Olomouc, Czech Republic.
authors: Ivan
authors: I
authors: Vařeka
authors: Department of Natural Sciences in Kinanthropology, Faculty of Physical Culture, Palacky University, Olomouc, Czech Republic.
authors: Milan
authors: M
authors: Elfmark
keywords: 2-D videography; biomechanics; kinematic chains; ski jumping