US Patent 7201707 Elliptical exercise machine with adjustable stride length

An elliptical exercise machine and methods for using the machine where the horizontal length of the stride of the ellipse can be adjusted by the user without the user having to alter the vertical dimension of the ellipse by an equivalent amount. The machine provides for alteration using an inverted pendulum arm which is driven by rotation of a rail and which in turn drives a footskate on the rail. The position for the driving of the inverted pendulum arm by the rail and the driving of the footskate by the inverted pendulum arm are adjustable relative to each other so as to provide for multiple different stride lengths in exercising. The machine may allow for this adjustment to occur during the performance of an exercise routine.