Some interesting facts about the respiratory diaphragm.
It originates from inside surface of ribs 6-12, the xiphoid process of the sternum, and the anterior surface of L1 through L3, and it inserts on itself. What does that mean?
Well, the respiratory diaphragm has a central tendon in the middle of the muscle and all the muscle fiber go toward that tendon. When the central tendon is drawn inferior, inhalation is initiated.
Another piece of information about the diaphragm is that it separates the thoracic cavity from the abdominal cavity.
Most of the abdominal muscles attach to the ribs as well, so if the abdominal muscles are shortened due to hypertonicity, weakness, or posture, some fibers of the diaphragm will be shortened as well while others will be lengthened.
A further interesting tidbit is that the upper fibers of psoas major join with the fibers of the respiratory diaphragm. This is called interdigitation. This also means that what effects the diaphragm will affect the psoas major, and vice versa. When we are focused on lengthening/softening/releasing psoas major, we must assess the respiratory diaphragm.
One last piece of information about the diaphragm, the fibers do not all work together. If one psoas is shortened, that side of the diaphragm might be pulled inferior, while the other side does not move. If the floating ribs are posterior on one side, the diaphragm fibers attaching to those ribs will be pulled posterior.
Releasing and balancing the diaphragm is fairly easy to do. Check out Full Circle’s SMRT: Abdominal video available in 3 ways at https://efullcircle.com/spontaneous-muscle-release-technique-abdomen/