Abdominal muscles

The external oblique, closest to the surface, extend inferiorly and medially, in the direction of sliding one’s four fingers into pants pockets.

Perpendicular to it is the intermediate internal oblique, extending superiorly and medially, the direction the thumbs usually go when the other fingers are in the pants pocket.

The deep muscle, the transversus abdominis, is arranged transversely around the abdomen, similar to the front of a belt on a pair of pants.

The linea alba is a white, fibrous band that is made of the bilateral rectus sheaths that join at the anterior midline of the body.

This part of the core plays a key role in stabilizing the rest of the body and maintaining posture.