Abstract: A method and apparatus for exercising the abdominal muscles where the exerciser is seated and the legs are spread apart and held in that position during the exercise which is accomplished by bending the upper torso forwardly and rearwardly through exertion of the abdominal muscles against a resistance offered by a weight stack. The machine includes a movement arm having a resistance pad engageable by the chest of the exerciser as the exerciser moves forwardly to perform positive work and rearwardly to perform negative work. The movement arm includes two parts one of which includes the resistance pad and is mounted to the other part by means of a spring mechanism so that the pad is spring mounted and may be moved to a raised position to allow easy entrance and exit from the machine. A cam fixed to the movement arm is connected to the weight stack pin by means of an actuating lever located below the weight stack.