A reversible resistance exercise machine for reversing the direction of applied resistance against a movable platform of an exercising machine. The exercise machine has a frame, a carriage movably positioned upon the frame, and a plurality of biasing members. A plurality of first tension connectors are accessible near the first end of the carriage and are adapted for removably attaching selected biasing members near the first end of the carriage to resist motion of the carriage in the first direction. A plurality of second tension connectors are accessible near the second end of the carriage and are adapted for removably attaching selected biasing members near the second end of the carriage to resist motion of the carriage in the second direction. A user selectable amount of force may be applied to the carriage to resist movement in either of the first direction and the second direction.