Transversus Abdominis
Abdomen & Core
Your deepest ab muscle — the 'natural weight belt.' Physical therapists love training this one.
Function
Compresses abdomen, stabilizes core
Origin
Internal surfaces of costal cartilages 7-12, thoracolumbar fascia, iliac crest, inguinal ligament
Insertion
Linea alba, pubic crest, pecten pubis
Innervation
Intercostal nerves T7-T12, subcostal, iliohypogastric, ilioinguinal nerves