When activated look for a discernible movement of the muscles in the lower leg and visible outwards and upwards movement of the foot. It is not sufficient to see only a slight movement in the muscles of the lower leg alone. The movement in both the lower leg and foot should be discernible.
A visible dorsiflexion is required for the full therapeutic effect and the setting required may change when the leg is bent or extended. Adjust the setting up or down as required with any change of position.