Fig. 3

Illustration of the results for right and left foot progression angles across the whole training protocol, estimated at each entire foot contact via inertial (blue lines) or optical (red lines) motion capture input. An offset correction is calculated during the first 60 s when participants are instructed to walk with straight toes and applied after that. A unique random target is provided for 120 s (mid-point of green dashed lines indicating the ±2° good step range), after 30 s of no target (rest) period