The effect of buckle closure and temperature on the in-vivo flexibility of ski-boots: a pilot study

摘要

Stiffness properties of ski-boots in forward/backward flexion are fundamental in characterizing their level of performance considering that they have to transmit control loads from the skier to the skis. Despite their importance, the mechanical characterization of the ski-boots still lacks of a standardized laboratory method. Ski-boot behavior can be influenced by several factors in addition to their construction, such as buckles level of closure and environmental temperature. The aim of the present work was to measure the "in-vivo" bending moment and the shell/tibia angle at two temperature conditions and two levels of buckles closure. A force plate, a portable dynamometric ski plate and two biplanar electrogoniometers allowed measuring the above mentioned parameters during simulated forward flexions as well as during real skiing on the slope of an expert skier. This allowed producing synchronous data of ski-boot hinge bending moment and of shell/tibia angle during skiing sessions that were not yet available in the literature. Results concerning the relationship between ankle bending moment and shell/tibia angle didn't show a correspondence between simulated flexions and real skiing: these findings will require further investigations to lead to possible standard laboratory test procedures simulating the real skiing.