An abdominal exercise device includes a frame, and upper and lower force receiving members movably mounted on respective portions of the frame and constrained to move in opposite directions. A person using the device is required to stabilize the device while seated on a conventional chair. A resistance device is interconnected between the frame and at least one of the force receiving members to resist movement of the members toward one another and/or to bias the members away from one another. The lower member is configured to support a person's feet, and the upper member is configured to support a person's hands and/or to engage a person's chest. The device facilitates a combination crunch and leg lift exercise that involves both a person's upper abdominal muscles and a person's lower abdominal muscles, and additional options are available to exercise a person's oblique muscles, as well.