CALCULATING CENTRE OF PRESSURE FROM MULTIPLE FORCE PLATES FOR KINETIC ANALYSES OF SPRINT RUNNING

  • Timothy Exell
  • David Kerwin
  • Gareth Irwin
  • Marianne Gittoes
Keywords: inverse dynamics analysis, accuracy, verification

Abstract

Force plates are relatively small compared to athletes’ step lengths during sprint running. A large number of trials are subsequently rejected when collecting force plate data, which could be reduced by using multiple force plates. The aim of this study was to determine the suitability of foot contacts occurring across the boundaries of two force plates for use in inverse dynamics analyses. Centre of pressure data for a loaded wheel rolling across two force plates were compared to known positions of the wheel measured using an automated motion analysis system. A mean difference of 0.0027 [±0.0024] m was found between centre of pressure location and the measured wheel position as the wheel crossed the boundary between plates. The centre of pressure error resulted in joint power errors ranging from 0.27% to 1.47% for the ankle, knee and hip.