A machine is for exercising the muscles of the lower back. The machine
includes a base frame and a resistance arm including a resistance pad
engaged by the user, the resistance arm coupled to the base frame at a
first rotation point and having a center of rotation about the first
rotation point. The machine further includes a seat frame member carrying
a seat, the seat frame member coupled to the base frame at one or more
seat rotation points and having a center of rotation about each of the
seat rotation points. The resistance arm and seat frame member are
rotated in opposite directions during a repetition cycle about the
respective first rotation point and at least one seat rotation point.