BodyCraft Strength Training System Exercise Manual page 49

Ab Crunch
Adjust the seat to the lowest position and the seat back to the upright
position. Attach the ab strap to the cable end located behind your head.
Drape the ab strap over your shoulders and hold it in place. Use your
abdominal muscles to crunch forward and downward. Return slowly.
Primary muscles worked: Abdominals (stomach).
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