Muscle · Core
Transversus abdominis
Musculus transversus abdominis
Reviewed by Dr. Ryan Rietz, D.P.T. and Dr. John Breyman, D.C.
The deepest of the four sheets of the abdominal wall, and the only one whose fibres run straight around the waist like a belt. It is not a mover: pulling a horizontal band tight cannot bend or twist the spine, it can only compress what is inside it. That is the whole point — transversus abdominis raises the pressure inside the abdomen and tensions the thoracolumbar fascia behind it, and the lumbar spine gets stiffer as a result. The founder's document lists it as the core bracing muscle, and puts it on the WEAK list for this region: it is the muscle that is supposed to switch on before you lift, and the one that most often does not.
Also known as
- TVA
- TrA
- deep core
- the internal corset
- deep abdominal muscle