Torques developed by different types of shoes on various playing surfaces.

The purpose of this investigation was to determine the effects of shoe type, playing surface, weight supported and stance position upon the torques developed at the shoe-turf interface. The study was predicated upon the assumption that many knee injuries are torque-related and due to foot fixation, either by rigid cleating or by excessive traction between the shoe and playing surface. A laboratory apparatus was designed to measure the torque developed by various shoe-surface combinations. Under investigation were 11 shoe types, three artificial surfaces and natural grass, two player weights, and two player foot-stance positions. Torque data were gathered using impact loading, with an impact energy that is probably often experienced under competitive playing conditions. Resulting data indexed the shoes according to the mean torques developed on each of the playing surfaces, and comparisons of torque data with field studies by other researchers suggested which shoe-surface combinations might be the most potentially hazardous.