Leg-specific Separation of Running Vertical Ground Reaction Force Signals

In this paper, we propose guidelines and techniques for optimally handling Vertical Ground Reaction Force (VGRF) signals acquired during running. For that endeavor, we developed an algorithm that performs leg-specific signal separation in an adaptive manner such that each VGRF signal is decomposed into two equally-sized time series each being specific to one of the two legs. Our technique was applied on single-channel VGRF signals recorded via instrumented treadmill during a 24-hour marathon performed by 12 athletes. The purpose of proposing such techniques lies in the fact that the VGRF signal carries combined data relevant to both legs' anatomical and physiological states and its analysis may only describe overall running characteristics, neglecting the importance of inter-leg symmetry in rehabilitation and performance analysis which requires leg-specific analysis.