Lie on your back on a decline bench and hold on to the top of the bench with both hands. Don't let your body slip down from this position. Hold your legs parallel to the floor using your abs to hold them there. Keep your knees and feet together. Slowly contract your abs, focusing on bring your pelvis up and in towards your chest Let your abs do the work! Slowly lower your pelvis to the starting position, keeping constant tension on the abs. Don't arch your back inwards while you are at the down position!