University of California, Berkeley, CA
Professor of Engineering and President, University of Maryland, College Park, MD
Pages: 19 Published: Jan 2000
By comparing the forces at the bindings required to ski normally to the forces recommended by the current setting standards, we evaluated the currently used method for selecting the ski-binding release forces for an individual. For 32 subjects (including beginning skiers through members of professional racing teams; 48 to 103 kg; 16 to 60 years of age), the lateral force at the toe binding and the vertical force at the heel binding were measured during skiing experiments. For each subject, the maximum lateral toe force and vertical heel force were measured in runs without falls and without binding releases.
For 20 of the 32 subjects, the current setting standards allow forces at the bindings that far exceed the forces required to ski in at least one release mode. Fifteen of the subjects generated maximum lateral toe forces during normal skiing that were less than 65% of the magnitude recommended in the current standards. For another 15 subjects, the maximum vertical heel force needed for normal skiing was less than 50% of the force recommended by the setting standards.
In order to improve the accuracy of the setting standards for the individual, we examined the relationships between the required settings and the variables used in the current standards (weight, height, age, and skier type) to select the settings. Multiple linear models that used skier weight, height, age, and skill level could not predict accurately the optimal settings for an individual (multiple R correlation coefficients were 0.57 and 0.73 for toe and heel settings). Furthermore, weight was found to be a poor predictor of the required settings, with all linear and quadratic correlation coefficients less than 0.46.
Nonanthropometric variables were considered for use in a predictive model for the best settings. Slope steepness and grooming were examined for a relationship with the forces generated during skiing, but no statistically significant relationships were found. Skier attitude, confidence, and skiing style appear to be related to the required settings. Measurements of the forces during low-velocity maneuvers before a day of skiing, which were found to generate high forces more often than downhill skiing and which incorporate skier confidence and style, could provide a better method of determining the settings for the individual skier.
ski biomechanics, ski safety, ski bindings, binding settings, minimum retention
Paper ID: STP12862S