Inter: between
Costals: ribs
Your intercostals are the muscles in between your ribs
that help us to breathe and also stabilize the rib cage.
For meat-eaters - these little in-betweeners are
aka: "the meat on your pork spare ribs"
Intercostals are divided into two groups:
External and Internal Intercostals
The fiber direction of these muscles are similar to
the internal and external obliques (abdominal muscles)
Muscle attachment points:
Origin: Inferior (bottom) border of the rib above
Insertion: Superior (top) border of the rib below
Muscle Action:
Internal intercostals: help you to exhale by drawing the ribs down, squeezing air and decreasing the space of the thoracic cavity (chest/torso)
External intercostals: help with inhalation by drawing ribs up - increasing the space in the thoracic cavity.