Objective: The aim of this study was to introduce a method for quantification of movement dynamics during active voluntary body weight transfer evoked by a sidestep after rehabilitation treatment. Methods: In our program healthy subjects (CTRL) and cerebellar patients (CBL) provoked sequences of active body weight transfers by performing sidesteps. The centre of vertical pressure (CVP) was recorded and the movement time of each sidestep was determined iteratively from the CVP-trajectory. The duration of the movement time was normalized to a common time interval template. From these data the time flow of mean velocity, acceleration and jerk was calculated. Results: The mean velocity curve of a control subject showed a system of three peaks characterizing the transfer of body weight, first to the stepping foot, then the stepping movement itself and finally, the shift of CVP between both feet after touchdown of the stepping one to restore equilibrium. In contrast, the mean velocity curve of a patient differed from control in several points: The transfer of body weight to the stepping limb was incomplete; the mean velocity during the main movement was lower and, most evident, two movements were necessary to restore equilibrium. Conclusions: The algorithms presented in this study allow automatic identification of the timing of the dynamic phases and calculation of the time flow of mean velocity, acceleration, and jerk for the active movement only. Supported by the "Else Kröner-Fresenius-Stiftung" (A12/07).