|Latin||intersectiones tendineae musculi recti abdominis|
|Gray's||subject #118 415|
The Rectus abdominis is crossed by fibrous bands, three in number, which are named the tendinous inscriptions (or tendinous intersections); one is usually situated opposite the umbilicus, one at the extremity of the xiphoid process, and the third about midway between the xiphoid process and the umbilicus.
These inscriptions pass transversely or obliquely across the muscle in a zigzag course; they rarely extend completely through its substance and may pass only halfway across it; they are intimately adherent in front to the sheath of the muscle.
Sometimes one or two additional inscriptions, generally incomplete, are present below the umbilicus.
If well-defined, the rectus abdominis is colloquially called a "six-pack." This is due to tendinous intersections within the muscle, usually at the level of the umbilicus (belly-button), the xiphisternum, and about halfway in-between.
An extremely well defined abdominal section can appear to be an "eight pack", as all eight sections of the abdominal muscle become defined. This definition is prominent among athletes with low body fat percentages, such as bodybuilders and swimmers.
- SUNY Labs 35:10-0104 - "Anterior Abdominal Wall: The Rectus Abdominis Muscle"
- SUNY Anatomy Image 7554
- Atlas of anatomy at UMich abdo_wall60 - "The Rectus Sheath, Anterior View & Transverse Section"
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.