Abstract: The present invention provides an abdominal exercise apparatus having an adjustable curved back support. The machine is used to produce an exercise that isolates, stretches, works, and develops the muscles of the abdominal wall (abs). The machine positions and supports the body to prevent it from unfolding at the hips, eliminating use of the thigh flexors and pain they cause from the exercise. Then it arches the back, which in turn extends the abs fully. In a preferred embodiment, the tension of extension of the abs is adjustable through positioning of back support.