Abstract: There is provided a drive assembly for converting the motion of a person running or jogging into mechanical motion to drive a machine or apparatus, such as self propelled apparatus like a bicycle, or stationary exercise apparatus. The drive assembly comprises a rotatable member, such as a crank arrangement, coupled to a frame of the machine and to stirrups, and where foot pedals are pivotally attached to each of the stirrups. A first pivot is connected between a stirrup and the rotatable member, and a second pivot is connected between the same stirrup and the frame. Preferably, a pivot axis of a foot pedal remains below the first pivot and the second pivot during motion of the foot pedal. Preferably, the pivot axis of the foot pedals trace asymmetric ovate paths during motion of the foot pedals. Motion of the foot pedals drive the rotatable member.