In a quick nutshell, the abdominal region is made up of just a few muscle groups:
- The Rectus Abdominis which is the section that people commonly refer to as the "six-pack", although in actual reality, it consists of 8 heads. The 7th and 8th heads are generally only visible when an individual has extremely low body fat, which is why you will sometimes see pictures of people with 8 packs!
- The Obliques are made up of the External Obliques on the side, and the Internal Obliques underneath them. Both run diagonally and are only really visible when the muscles are well developed and subcutaneous fat deposits are very low (more on that later).
- The Transversus Abdominis which is located deeper within the abdominal complex and is not nearly as visible to the naked eye as the other muscles.