Patent ID: 8079937

Claim:
An exercise apparatus comprising: a frame; a footpad for supporting a user's foot; a linkage for coupling the footpad to the frame and for guiding the footpad in a closed path in response to a force applied to the footpad by the user's foot, the linkage including a rotatable member having an angular position indicative of a position of the footpad within the closed path, wherein the linkage adjusts a dimension of the closed path in response to an electrical control signal supplied as input to the linkage; and a control system for monitoring the angular position of the rotatable member, for monitoring the force applied to the footpad, and for generating the control signal such that the linkage adjusts the dimension as a function of the monitored force on the footpad and of the angular position of the rotatable member, wherein the control system controls the control signal such that when a magnitude of the force is outside a magnitude range, the linkage alters the dimension while the angular position of the rotatable member is within a position range and otherwise refrains from adjusting the dimension.