Footstep adjustments during walking and turning.

<p>Schematic drawing of representative footstep adjustments for (a) straight walking, (b) step strategy during a right turn (i.e. first turning step with the foot that was on the same side of the body as the turning direction), and (c) spin strategy during a right turn (i.e. first turning step with the foot on opposite to the turning direction). Black foot prints illustrate straight walking steps and grey foot prints show the first turning step. Note that, for the spin strategy, the first turning step (i.e. left/external foot) crossed over and landed medially compared to the progression of the preceding step (i.e. right/internal foot). The solid arrow and the dashed arrow show step width and pelvis lateral displacement with respect to the line of progression of the stride (black line), respectively.