Reference: B Purcell, J Channells, D James, R Barrett, Use of Accelerometers for Detecting Foot-ground Contact Time During Running , PROCEEDINGS-SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 6036, 603615
Abstract: A biomechanical variable of interest to sprint coaches is foot-ground contact time. Contact time can be easily measured in a laboratory environment using a force platform, but is difficult to measure in the field. The focus of this paper is on the development and validation of an accelerometer-based method for estimating contact time during sprinting that could be used in the field. Tri-axial accelerometers were mounted on the tibia of the right leg of 6 subjects who performed maximal running trials from a stationary start, and running trials at a range of steady state speeds (jog, run and sprint). Ground contact times were measured using a force platform, and estimated from 3D accelerometer data. The mean errorbetween the force plate and accelerometer-based measures of contact time were 0 ± 12 ms, 2 ± 3 ms, and 1 ± 1 ms for the jog, run and sprint. For steps 1, 3 and 5 of the acceleration phase of the maximal sprint the mean errors were 8 ± 9 ms, 2 ± 5 ms, and 0 ± 1 ms respectively. Overall it was concluded from our analysis that close estimates of contact time during running can be obtained using body mounted accelerometers, with the best estimates obtained in conditions associated with the highest accelerations.