An exercise machine comprises an arm support, including: a carriage configured to slide within a track attached to the exercise machine; and a support assembly that floats the carriage relative to the track, wherein the support assembly is disengaged by the application of force via the arm. An exercise machine comprises a rotatable column, wherein the column supports an arm, and a gear detent mechanism to support a discrete number of positions for the rotatable column. An exercise machine comprises a tiltable arm, and a mechanism to support a discrete number of positions for the tiltable arm.