an abdominal bench having an extendable and retractable assist and resist assembly that will , depending upon how it is connected , provide variable levels of assistance forces to help pivot a torso section of the bench into an upright position and / or variable levels of forces that will resist the pivoting of the torso section . the extendable and retractable assist and resist assembly can include one or more elastic members that can work solely or in tandem to provide the assistance and resistance forces .