Abstract: An infinitely adjustable elevation system for a treadmill is disclosed. The treadmill has a frame having a pair of spaced side rails and a pair of spaced uprights extending upwardly from the front ends of the side rails. The elevation system comprises a pair of generally vertical, rigid, elongate members, each of which is carried by a respective side rail and which is movably mounted within a respective upright. Each of the elongate members is movable in a generally axial, vertical direction relative to its side rail between a retracted position in which the jogging surface of the treadmill is in substantially horizontal position, and an extended position in which the front of the treadmill (and the jogging surface) is inclined upwardly.