Supports abdominal wall, assists forced expiration, aids raising intraabdominal pressure and, with muscles of opposite side, abducts and rotates trunk
external oblique abdominus
Supports abdominal wall, aids forced expiration and raising intra-abdominal pressure. Conjoint tendon supports posterior wall of inguinal canal
transversus abdominus
Flexes trunk, aids forced expiration and raise intra-abdominal pressure
rectus abdominus
Reinforces lower rectus sheath
pyramidalis
Fixes 12th rib during respiration and lateral flexes trunk
quadratus lumborum
Supports abdominal wall, assists forced respiration, aids raising intra-abdominal pressure and, with muscles of other side , abducts and rotates trunk. Conjoint tendon supports posterior wall of inguinal canal
internal oblique abdominus
Inspiration and assists in raising intra-abdominal pressure