INTRODUCTION: What makes one athlete fastest? Is it science or art? In this paper, the biomechanical analysis of an athlete's technique is used to address these questions. Humans have long been obsessed with the artistic appearance of an athletic performance; this "kinematic Obsession" can often obscure the underlying forces - the science of skilled human movement. The analysis shows that in ski racing, a turn that is considered most visually acceptable is not always the fastest turn. In addition, the fastest turn does not necessarily produce the winning Overall course time. Here underlies the art of global race strategy choice. METHOD: Fusion Motion Capture (FMC) was used to capture the motion of a New Zealand athlete performing laps through a giant Slalom course. The complete kinematics and kinetics of the athlete were calculated using algorithms developed by the author in MATLAB. Fusion Motion Capture uses GPS, IMUs and pressure sensitive insoles, more details are available in a poster 'FUSION MOTION CAPTURE: ACCURACY OF MOTION CAPTURE WITHOUT CAMERAS FOR ALPINE SKI RACING', a poster presentation at this conference. Key parameters from the athlete's performances including; maximum effective inclination, wind drag, snow friction, and ground reaction force were extracted. The net external powers and joint torques and powers were calculated using athlete specific body segment inertial Parameters. These were compared to gate split times to investigate the underlying causes of exceptional performances within each run. RESULTS: Selected results show the ground reaction power between gates 5 and 7. Global race strategy can be visualized by animations comparing several runs. DISCUSSION: The more effective turns were most likely a result of greater positive ground reaction force power and work. This observation is independent of speed, gate spacing, course conditions, or stylistic constraints. Positive power was created by higher effective inclination of the athlete at the turn apex and a global strategy that makes use of subtle changes in the terrain. A method for calculating global race strategy is being developed. We can now optimize global strategy on flat sections of a course (where there is minimal skidding) based on the athlete's parameters. Science provides us with a description of how to ski faster. However, the athlete's skilled performance, instinctive reactions to perturbations, and changing course conditions remain artistic. This is confirmed by the fact that as of now, we still are unable to build robots that can outperform a human skier.
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