Will help to tone and strengthen a person’s abdominal muscles, as well as the person’s core muscles, which is essential for a fit body. Ab crunches are commonly used to strengthen the abs and the core muscles of the body, though there are also a number of modified crunches and exercises that can be performed to tone abs and reach the goal of having stronger stomach muscles.
A reverse crunch is a modified version of an abdominal crunch, which a person used to tone different areas of the abdomen. This exercise is done with legs up in the air, and the muscles of the abs are contracting when the person performing a reverse crunch lifts his hips in the air. This is usually repeated 12 to 15 times with three separate sets.
The bicycle crunch is a modified version of the ab crunch that uses the momentum of the legs in order to exercise the abdomen and obliques. With a person lying down on his back, he or she raises his legs in the air with hands behind the head. The person then shifts his legs back and forth in a bicycle motion.
Oblique crunches are designed to focus on the internal oblique muscles and the external oblique muscles near the abdomen. This is usually performed by lying on one’s back with hips on the side so that the obliques can be targeted.
Crunches can also be performed with equipment, such as an exercise bench or a exercise ball, which can provide support and allow for more difficult ab exercises to be performed.