On the control elements of voluntary movements.

TL;DR: The scaling of APA was based on the anteroposterior and lateral displacements of COP and the temporal sequence of selected muscle activities, which ultimately controls the direction of steps.

TL;DR: It is concluded that ML corresponds to the "true" reaction time while PA covers the earliest part of the motor response.

TL;DR: An internal image of normal posture exists that automatically controls the distribution of the postural tone and consequently the center of gravity, which permits the maintenance of equilibrium during the performance of the movement.

TL;DR: The motor control adaptation seems to reflect a strategy of improved coordination between the trunk muscles with the unilateral shoulder movement, which does not seem to be a valid mechanism of action for specific trunk exercise rehabilitation programs.