The Ab Shaper is a product made by Weider, and assists the user in performing a variety of exercises to shape the lower, upper and oblique abdominal muscles.
The Weider Ab Shaper is highly recommended by Popular Mechanics, because the device "exemplifies a clever design and durable, sturdy construction," as well as being affordably priced.
Doing crunches and sit-ups to exercise abdominal muscles is effective, but using a machine such as the Ab Shaper puts more focus on the abs and less on other parts of the body.
Lay your Ab Shaper onto a flat area of the floor. Lie back and place your head onto the headrest.
Bend your knees and place your feet hip-width apart. Make sure your back is flat on the floor.
Grab onto the handles that are above your shoulders with the palms of your hands facing up and forward.
Pull your shoulders and head up 45 degrees from the floor, making sure to tighten your abdominal muscles. You should be focusing all of your effort into contracting your abdominal muscles, and not using your back to pull yourself up. While pulling up, keep you lower back on the floor.
Hold the crunch for five seconds, then bring your head and shoulders back to your starting position. Repeat 10 times without pausing. You may increase repetitions as you see fit.