Figure 2.

Example of the main biomechanical traces obtained for one subject during gait initiation gait (one trial) under the Symmetrical condition. y”CoM, y’CoM, yCOM, yCoP: mediolateral center-of-mass (CoM) acceleration, velocity and displacement, mediolateral center-of-pressure (CoP) displacement, respectively. x’COM, xCoP: anteroposterior CoM velocity and anteroposterior CoP displacement, respectively. T0 indicates the onset variation of the y”CoM trace from the baseline. HO and FC: swing heel-off and swing foot-contact, respectively. F and B indicate forward and backward movement, respectively. ST and SW indicate stance limb and swing limb, respectively. x’CoM_HO, x’CoM_FC, x’CoM_max, xCoP_max: anteroposterior CoM velocity at heel-off, at foot-contact, at the end of the first step and maximal backwards CoP shift, respectively. y’CoM_HO, y’CoM_FC, yCoM_max, yCoP_max: mediolateral CoM velocities at heel-off, at foot-contact, maximal mediolateral CoM displacement towards the stance leg and maximal mediolateral CoP displacement towards the swing leg during anticipatory postural adjustments (APA). APA and EXE: time windows for APA and step execution.