A system including a platform having a receptacle adapted to a bottom of a shoe or foot； securing mechanism, associated therewith； a sole for contacting a ground surface； a mechanism associated with the sole and a platform bottom, including: motor and a thrusting element, activated by the motor, the thrusting element adapted to move between the sole and the platform to apply an upward force against the platform bottom, thereby changing a platform height with respect to the sole； a sensor device adapted to associate with a lower limb, and to produce a locomotion data signal, and a microprocessor, operatively connected to the sensor device and motor, adapted to: receive locomotion information based on the signal； process the locomotion information to determine a locomotion phase, and control a timing of the mechanism, based on the determination, to change the height during a locomotion swing phase.
