Quantifying coordination in kinematic data : a running example

To compare methods of quantifying coordination, one healthy male participant was filmed in three dimensions at 120 Hz whilst running at 3.8 m/s. The knee and hip angles and angular velocities of the left stride, normalised to 100 data points, were analysed using continuous relative phase (CRP) and cross correlations (CC). The phase planes were normalised to -1 and +1, and the component phase angles (I) for each segment calculated with the range O°< I <180°. CC indicated a strong linear relationship between the knee and hip with a lag of 19% of the stride time in the hip data (r =0.85). The relationship was linear and non-linear at different phases, which may warrant a separate analysis of phases of running to identify coordination. CRP of one trial did not provide any meaningful indication of coordination, but the variability of CRP over several trials may provide an alternative indication of stability of coordination.