This is the Rectus Abdominis
AKA “Abdominal Muscles” and “Abs”
the superior edge of the pubis bone
the pubic symphysis in the pelvis.
The inferior edges of the costal cartilages of the fifth through seventh ribs
The xiphoid process of the sternum.
performs the important task of flexing the torso and spine in the abdominal region.
It does this by pulling the rib cage closer to the pelvis.
The rectus abdominis can also tense to contract the abdomen without moving the torso, as in sucking in one’s gut.
Assists in breathing.
when forcefully exhaling, as seen after exercise as well as in conditions where exhalation is difficult such as emphysema.
It also helps in keeping the internal organs intact and in creating intra-abdominal pressure, such as when exercising or lifting heavy weights, during forceful defecation (bowel movements) or childbirth.
What Gives the “Abs” Their Shape?
Bands of connective tissue called the Tendinous Intersections traverse the Rectus Abdominis, which separates this parallel muscle into distinct muscle bellies.
Between the rectus abdominis muscles is a thick mass of white fibrous connective tissue called the Linea Alba that unites the abdominal muscles of the left and right sides.
The outer, most lateral line, defining the “abs” is the Linea Semilunaris (attachment sites for the external oblique and the transverse abdominis).