If you're looking for a lean midsection, ab exercises might be on your agenda. However, ab exercises don't directly burn belly fat and if you're carrying excess fat, you won't get that lean six-pack no matter how many ab exercises you do, notes Steve Holman, editor of "Iron Man Magazine." Excessive ab training could even make your core look bigger.
Your core is made up of an inner and outer section. The inner section comprises your pelvic floor muscles, multifidus and transverse abdominis. Between them, these muscles provide stability and support for the whole of your body. On top of this are the obliques and the rectus abdominals -- these are the muscles that make up that holy grail of physique fitness: your six-pack.
When training a muscle to the point of fatigue, you break down muscle tissue. This broken down tissue then regrows bigger and stronger, provided you get enough rest and nutrition. Therefore, any exercise that stresses your abdominals can potentially lead to mid-section muscle growth and make your core look bigger.
Inner vs. Outer Core
Training your inner core muscles -- the multifidus, pelvic floor and transverses abdominis -- is unlikely to lead to noticeable growth, as these are the deep muscles and can't be seen on the surface. The best way to target these is with stabilization exercises like the plank, side plank and standing cable press, writes strength coach Eric Cressey in "Maximum Strength." By performing outer core exercises like the traditional crunch, sit-up, leg raise or side bend, however, you are breaking down muscle tissue and setting yourself up for a bigger, bulkier mid-section.
Core Training -- The Right Way
The shape and size of your abs are mainly determined by genetics and even posture, according to strength coach Deborah Mullen, so if you want a flat stomach, concentrate on standing tall and holding your core tight. Training your core in the right way can also relieve and prevent lower back pain, notes Len Kravitz of the University of New Mexico. Your abs are also very thin, adds Kravitz, meaning the idea they'll get too big is unlikely. Stick mainly to inner core exercises like planks to improve posture, strength and prevent injuries.