ABSTRACT
Force platforms are often used to assess the ground reaction forces occurring in sports performance. The top plate struck by the foot is usually constructed of metal. Although training shoes are often worn, there are many athletic and field sports which require the use of spiked shoes. To measure ground reaction force in athletic and field situations it is necessary to have a surface covering which allows the subject to use normal sports footwear. Knowledge of the effect of using an ecological surface cover upon primary ground reaction force measures is necessary to aid scientific experimental analysis. Although static electromechanical tests are used to assess force platform measurement performance, there is a role for dynamic ecological measurement studies (Nigg, 1990). The concept of population preferred cadence and associated speed (Murray et al., 1966) was an underlying concept of the proposed study and was adopted in an effort to improve the reproducibility of ecological testing. However, in the experimental design it was also recognized that adoption of preferred cadence may result in individual preferred speeds which arise because of anthropometry and environmental factors. This study aimed to investigate the effect on peak ground reaction force measures of covering a force platform, mounted within a polyf1ex track, with a polyflex sports surface (International Amateur Athletic Federation standard) using an aluminium base plate interface. It was hypothesized that there would be no difference in the peak ground reaction force measures when the specially constructed polyflex cover was used in comparison to a metal top plate.
