Redesigning Figure Skating Boots To Reduce Impact Forces

Abstract

Figure skating has evolved into a highly specialized and athletic sport with difficult triple and quadruple jumps increasingly becoming the primary focus. Skaters are spending more time practicing jumps and overuse injury rates show an associated increase. The current rigid leather skating boot severely restricts ankle motion, reducing the body's ability to absorb damaging landing stresses. Modifying the current skating boot by introducing an ankle articulation may help reduce peak transient forces during landing. PURPOSE The purpose of this study was to test the ability of an articulated skating boot to attenuate ground reaction forces during landing. It was hypothesized that articulated figure skates would reduce peak forces as well as loading rates when compared to traditional boots. METHODS Prototype articulated boots were manufactured by Jackson Ultima Skates inc. Nine US Figure Skating juvenile-level or higher figure skaters from the surrounding area were tested in off-ice simulated jump landings from a 30cm platform onto a force plate. Kinetic and kinematic data were collected and analyzed from skaters wearing standard skating boots and, after a brief training period, wearing articulated boots. A repeated measures ANOVA was used to determine significant differences (alpha=.05) in ground reaction forces, loading rates, and several kinematic variables. RESULTS Peak heel impact forces and loading rates decreased significantly in the articulated boot. Ankle plantarflexion and boot/ice angles at impact increased while the total jointfiexion at impact decreased. There were no statistical changes in toe impact force, jump height, and hip and knee angles at impact. CONCLUSIONS The majority of skaters used the increased range of motion in the articulated skates to effectively reduce landing forces and loading rates. However, a few showed very little change between conditions, even with increased ankle plantarflexion and boot/ice angles at toe contact. In some skaters, the ankle musculature was apparently not utilized to stiffen the ankle during the impact phase. The findings suggest that some skaters attempt to utilize the ankle, while others do not, and that some retraining may be necessary to decrease landing forces.