The Cubii mimics the movement of a regular elliptical trainer without the upper body component. That said, the Cubii won't work the glutes, hamstrings, and quads as much as a regular elliptical does because it can only be used while you're seated. Due to the angle at which your legs and feet fit into the pedals, the Cubii will primarily engage the muscles in your lower legs like your calves and tibialis anterior, which is the muscle that runs along your shin.