Issue link: https://www.massageandbodyworkdigital.com/i/1060121
68 m a s s a g e & b o d y w o r k j a n u a r y / f e b r u a r y 2 0 1 9 The transversus abdominis (and the internal oblique as well) form a horizontal myofascial belt to contain the organs, and cuddle them up safely against the spine. Courtesy John Hull Grundy. The belt in the back, the deepest lamina (layer) of the thoracolumbar fascia, ties the abdominals to the ribs, hips, and especially the transverse processes. Tone in the abdominals contributes to lumbar stability through this belt. Courtesy John Hull Grundy. 2A 2B The transversus abdominis belts around the waist, hugging the organs to the lumbar spine, stiffening the thoracolumbar fascia, and stabilizing the sacroiliac (SI) joint—quite a list of benefits for a toned transversus (Images 2A and 2B). This contrasts to what happens when the belly sags over the pubic bone, so that the organs pull the lower back forward and core support is lost. The transversus abdominis is important for sure, but—being one belt for both sides—it can either stabilize both sides at once, or neither. Walking or running, for instance, requires that one side of the hip/pelvis complex— the SI joint in particular—be locked into force closure, while the other leg swings forward, unlocked and free. In the next step (in other words, every couple of seconds), this must reverse, with the free side closing into stability, and the formerly stable side unlocking into freedom. This alternating stability and mobility from one side to the other could be called functional core support or dynamic core support, and it is a different animal that is going to require alternating tension in muscles other than the transversus abdominis and pelvic floor. "Oh, great, I've been toning my core for years now. Are you saying I have to strengthen other stuff?" Yes. Such dynamic force closure and release of the SI joint is a complex process involving the tone and timing of the piriformis and gluteus maximus, as well as the abdominals, but here we want to emphasize a muscle complex that has gotten too little press in the gallons of ink spilled over this important concept of core support. That combination is the psoas-diaphragm "cobra" on either side of the spine (Images 1A & 1B). COUPLING THE PSOAS AND DIAPHRAGM We will get to the anatomy and function of the cobra, but consider for a moment the centrality of the psoas and diaphragm. • Both muscles attach to the front of the spine, right in front of the T12–L1 "universal joint" of the spine, where the strong flexion/extension of the lumbars meets the rotating T-spine with its floating ribs. • Just in front of where these two muscles interface lie the kidneys (those ancient organs central to the definition of the self ) with the adrenal glands (those moderators of alarm), sitting on top of the kidneys like rain hats.