Skip to content

Transversus abdominis



Muscle Type

  • Phasic
    • Weakens when overactivated


  • Postural distortion of pelvis
  • Dysfunctional gait
  • Loss of abdominal tone
  • Gas, bloating, belching, heartburn
  • Vomiting, diarrhea


  • Postural faults
  • Breathing dysfunction
  • Overuse and strain
  • Trauma
  • Environmental stressors such as cold and damp
  • Nutritional deficiencies
  • Surgery and resulting scars
  • Viscerosomatic influences as a result of visceral disease
  • Viscerosomatic influences resulting from digestive disturbance
  • Emotional stress


Short version

Detailed version

Important functions

  • The oblique abdominals work as postural muscles
  • Phasic muscle group (which weakens during dysfunction)
  • The abdominal muscles play a significant role in positioning the thorax and in rotating the entire upper body
  • They are also known to play a key part in spinal stabilization and intersegmental stability, particularly the transversus abdominis
  • Rectus abdominis, external and internal obliquues and transversus abdominis are inolved in respiration due to their role in positioning the abdominal viscera as well as depression of the lower ribs, assisting in forced expiration and coughing

Notes of clinical importance

Increased tension in the muscle may cause problems with

  • Breathing
    • The abdominals depresses the rib cage, which causes a restriction to elevation of the rib cage, which again can cause problems with deep breathing
  • Back pain
  • Neck pain
  • Decreased neck rotation
  • Headaches

Too low tone in the muscle may cause problems with

  • Anterior tilt of the pelvis causing increased lumbar lordosis
  • Lower back pain

Clinical tests

Measure The Ribcage During Maximum Exhalation And Inhalation

  • In young healthy adults, the ideal change should be about 7 cm, less than 5 cm is not optimal
  • With age there will be a decline in the overall difference between maximum exhalation and inhalation


  • When the abdominals locks the rib cage into depression, this causes problems for the Scaleni which is supposed to elevate the rib cage. This forces the Scaleni to increase it's force in order to prevent further depression

Connected Myers lines

Spiral line

  • Splenius capitis and cervicis
  • Rhomboid major and minor
  • Serratus anterior
  • Obliquus externus
  • Abdominal aponeurosis, linea alba
  • Obliquus internus
  • Tensor fascia latae, iliotibial tract
  • Tibialis anterior ( ankle extensors)
  • Peroneus longus
  • Biceps femoris
  • Sacrotuberous ligament
  • Sacrolumbar fascia, erector spinae


  • Compression of abdomen:
    • Obliquus externus
    • Obliquus internus
    • Rectus abdominis
    • Pyramidalis
    • Quadratus lumborum
    • Diaphragma
  • Forced expiration:
    • Rectus abdominis
    • Obliquus externus
    • Obliquus internus
    • Latissimus dorsi
    • Serratus posterior inferior
    • Quadratus lumborum
    • Iliocostalis lumborum


To forced expiration:

  • Diaphragma
  • Scalene
  • Parasternal intercostalis internus
  • Levator costorum
  • Upper and lateral intercostalis externus
  • Sternocleidomastoideus
  • Upper trapezius
  • Serratus anterior
  • Serratus posterior inferior
  • Pectoralis major
  • Pectoralis minor
  • Latissimus dorsi
  • Erector spinae
  • Subclavius
  • Omohyoid