Anatomy of the Core

Definition and Muscles

• The body, minus arms and legs. • The torso, pelvis, and hips.• Major core muscles: pelvic floor, transversus

abdominis, multifidus, internal and external obliques, rectus abdominus, erector spinae, longissimus thoracis and the diaphragm.

• Minor core muscles: latissimus dorsi, gluteus maximus,adductors and trapezius.

http://en.wikipedia.org/wiki/Core_(anatomy)

Function

• The core stabilizes the thorax, spine and pelvis• The core aligns the spine, ribs and pelvis both

during stasis and movement• A strong core supports optimal posture and

protects the lower back• Core muscles assist breathing• The core provides support for the internal organs

Rectus Abdominus• 2 muscles, long flat fibers of which run

vertically from ribs to pubis• Segmented by ligaments• Required for spinal flexion• Assist breathing• Create intro-abdominal pressure, which aids

lifting• Help keep internal organs intact

Transversus Abdominis (TA)

• Flat, triangular muscles that runs between hips and ribs

• Fibers are horizontal

• Provides stability to trunk in lateral flexion

• Supports breathing by exerting pressure during exhalation

External Obliques

• Flat muscles located on lateral front of body, running diagonally in V shape from ribs to pubis

• Relatively small in size• Assist trunk and spinal flexion and rotation,

pulling chest down and compressing abdonimal cavity

• Support exhalation and the contents of the abdomen

Internal Obliques• Interior to external obliques and external to TA• Run on a diagonal, medial to lateral, sternum to

pelvic bones• Forces exhalation by compressing internal organs

up and into lungs, which in turn compresses lungs and forces air out

• Acts in concert w/external obliques on opposite side to rotate and flex the trunk by pulling the rib cage down toward the hip and back on the same side

Underneathand behind, alsosupporting the axial skeleton,is the psoas. And posteriorto this is the quadratus lumboram,the QA, which becomesover worked and sore if the core is not strong.

Multifidus can also become stressed ifour anterior core muscles are underused.