After attending a workshop with Richard Freeman I gained a new awareness of psoas major anatomy. In particular I was forced to learn how the psoas attaches to the 12th rib, and kidneys as well as the diaphragm. (Most anatomy texts fail to mention this connective tissue connection.)
I also learned a reclining psoas stretch.
For the reclining psoas stretch he had us laying down on our back with one knee hugged to the chest. The other leg was straight with the inner thigh pressing down.
We stretched the psoas major on the straight leg side by reaching the 12th (lowermost) rib away from the pelvis while at the same time reaching the arm past the head. (Think of the ribs, shoulder and arm all reaching away from the pelvis.)
We stretched the psoas muscle on the straight leg side. My feeling is that hugging the knee helped to tilt the pelvis rearwards and flatten the lumbar spine.
You could also reach both legs forwards and both arms back though as you can see from the picture below, it's a little bit more difficult keeping the low back flat to the floor.
Once I felt the effectiveness of lifting the 12th ribs while doing these psoas stretches, my thoughts were along the lines of:
"Holy shit, I always thought the psoas attaches to the lumbar spine. I knew it attached to the 12th thoracic vertebrae but I never even considered the implications of it being attached to the 12th set of ribs. Why didn't I think of that (damnit). Lifting the 12th ribs to stretch the psoas..."
Later on I was looking through my limited selection of anatomy books (The Anatomy Coloring Book, Anatomy of Movement) and none of them mentioned an attachment of the psoas to the 12th set of ribs.
I looked at an online edition of Gray's anatomy. It also bore no mention of the aforementioned attachment of the psoas to the 12th set of ribs.
Another thought occurred to me. I thought that to lift my 12th set of ribs I was using levator costalis. Subsequent testing on myself seemed to indicate that while the levator costalis do lift the back ribs, the feeling I had when focusing on just the 12th rib was different than that which I got when lifting all of my "back" ribs.
So I asked myself, since it probably wasn't the levator costalis, what does cause the 12th set of ribs to lift while at the same time creating a feeling of openness behind the kidneys?
In his workshop Richard Freeman talked about "lifting" the back of the diaphragm. I came to the conclusion that he wasn't talking metaphorically. He was actually telling us to use diaphragm to pull upwards on the 12th set of ribs.
The 12th set of ribs, along with the 11th set, are both floaters or "floating ribs". They have free ends. All of the other ribs form complete loops, whether they attach to the cartilage of the costal arch at the front of the ribcage or the sternum. The 11th and 12th sets of ribs do not attach to either or these. And that's why they are also known as "floating" ribs.
And by the way, another way to think of these ribs, the 12th particularly, is that they form the bottom of the back of the ribcage.
So what had this to do with stretching the psoas major, especially since the psoas doesn't attach to the 12th rib?
That was what I tried to figure out.
I tried to figure it out because when I did pull the bottom of the back of my ribcage away from my pelvis I got a stretching sensation. Not only that, in forward bends, when I focused on drawing the 12th rib away from my pelvis it helped to make my forwards bends deeper. And I assume it did this by somehow lengthening the psoas.
And so reaching the 12th set of ribs away from the pelvis could either help me stretch the psoas or lengthen it in such a way that it had room to contract effectively, helping my forward bends.
I had to look at the kidneys to find out that the connective tissue that wraps the kidneys connects to the connective tissue of both the psoas major and the quadratus lumborum.
Connective tissue, or fascia, also connects the kidneys to the diaphragm.
You could think of the kidneys as "hanging" from the underside of the diaphragm. More specifically, they hang from the back of the diaphragm. This means that when that part of the diaphragm lifts, the kidneys pull up with it. When that part of the diaphragm descends, the kidneys go down as well.
Now usually, when I think of the respiratory diaphragm activating, I think of it moving downwards. If you do diaphragmatic breathing, when you inhale you contract the diaphragm which causes it to move down and then that forces your abdominal organs downwards. These organs, needing room to move then press forwards on the front of your belly causing your belly to expand when you press your diaphragm downwards.
However, the diaphragm is anchored by ribs 7 through 12. In order to push the abdominal organs downwards when it contracts, it pulls upwards on the ribs at the same time.
(If you have trouble visualizing or understanding this, think of flying a kite. The wind pulls the kite one way, you, while holding the string, pull the kite in the opposite direction.)
For myself, if I pay attention to my ribs when breathing "diaphragmatically" what I can feel is my front ribs pulling upwards when my diaphragm contracts down.
However, if I focus on my back ribs, particularly the 12th set of ribs, I can cause them to lift... if I focus on lifting them.
What this indicates to me is that the fibers of the diaphragm can function, to a certain extent, individually. We can choose to specifically activate the fibers of the diaphragm that attach to the 12th set of ribs.
These fibers are important not only because they attach to the 12th set of ribs. I'm guessing that it is these fibers that the renal fascia attaches to.
The renal fascia is the connective tissue that connects the kidneys to the bottom of the diaphragm. If my "guess' is correct, then by activating the fibers of the diaphragm that attach to the 12th set of ribs, not only does the 12th set of ribs get pulled up, the kidneys get pulled up with them.
But guess what.
The renal fascia also connects to the fascia that covers the psoas Major (and less relevant to this conversation, the fascia of the quadratus lumborum.) It may be that via this connective tissue connection, that when the kidneys are lifted (by the diaphragm), they pull up on the fibers of the psoas (and quadratus lumborum) at the same time. The result it that lifting the kidneys via the diaphragm helps to stretch the upper portion of the psoas upwards (towards the head.)
Lets recap this understanding of psoas major anatomy.
While it feels like it is possible to lift just the 12th rib, focusing on lifting all ribs may cause the 12th rib to lift even more, thus increasing the stretch while doing psoas stretches.
Interestingly enough, the kidney meridian has a pathway that runs up the back of the inner thigh. Externally it then travels up the front of the body either side of the center line. However, an internal path travels up and back to the kidneys before doubling back to connect to the external path.
It may be that the internal path of the kidney meridian is in part via the connective tissue of the psoas. Via this connective tissue, the kidney meridian connects to the kidneys.
Knowing that the psoas connects to the 12 set of ribs via the renal fascia gives a reason for lifting the back ribs while stretching the psoas. And this can be true in either the full body laying or standing stretch but also in psoas stretching poses like high lunge and upright pigeon.
If you want to use either of these poses as psoas major stretches, then lift the ribs, in particular the back ribs, and in particular the ribs directly behind the kidneys.
But in order to stretch the psoas major you need to do more than just pull on one end. You also need to anchor the other end to do psoas stretches effectively.
My assumption at present is that the connective tissue that covers the psoas and quadratus lumborum is tissue that moves with the muscles in question so that when, for example, the psoas major, contracts, it can pull the kidneys, via the renal fascia downwards. (This is as opposed to connective tissue that covers the muscle without moving with the muscle. This might be the case with connective tissue that separates muscles from each other.)
The psoas major could also be activated in such a way that it pulls downwards on the fibers of the diaphragm that the renal fascia is connected to. This could mean that the psoas can affect breathing where the diaphragm is concerned. However I believe that fibers of the diaphragm can be activated independently, as if the diaphragm is a collection of muscles with a unified purpose. As an example, prior to learning to lift my back ribs, I could activate my diaphragm in such a way that it only pulled upwards on the front of the ribcage. Now it seems that I can activate it in such a way that it pulls up on the back ribs. (Note that this may be due to other muscles also activating or relaxing.)
This would mean that even though they are connected the diaphragm and psoas major can have some independent functions. But it also means that they can affect each other.
It also means that the ribs are also affected by the state of the diaphragm and via it, the psoas.
So, although breath and psoas function can be separate from each other, you may find that whether stretching the psoas or using it (to bend forwards) you may find it helpful initially to synchronize your actions with your breath.
When you are comfortable synchronizing actions with your breath you can try stretching or activating your psoas major without breath synchronization. The suggested intent is to be able to do both options easily.
(And so to that end you can experiment with linking psoas and breath actions. And you can experiment with using the psoas independently of the breath. Can you keep your back ribs lifted while continuing to breath? I'll suggest that you can.)
While the focus on this article is stretching the psoas major, if you are trying to use your psoas, to perhaps help while doing a forward bend, you can lift your back ribs, in particular your 12th set. The idea behind this is that in order to contract effectively any muscle needs room to contract. If you are trying to use your psoas, then you can help to activate it by lengthening it. And you can do this by using your diaphragm to pull up on the kidneys and the 12th rib. The psoas then has room to pull the thigh towards the chest closing the front of the hip joint.
Question, is the 12th rib really that important?
Actually, more than anything, feeling the 12th rib moving away from the pelvis is a good indication that you've activated your diaphragm. And that is really the important point when doing psoas stretches. When the back of the diaphragm pulls up, it pulls up on the kidneys and via them the psoas.
The lower end of the psoas major attaches to a point on the inner edge of the thigh bone called the lesser trochanter. This bony prominence it located just below the neck of the thigh bone (femur) and towards the back of the shaft. This point is at about the same level as the bottom of the pelvis.
From its upper attachment the psoas angles forwards and downwards towards the front of the pelvis. It wraps around the pelvis and passes back and down to the lesser trochanter.
To lengthen the the psoas you can pull the kidneys away from the front of the pelvis and at the same time pull the top of the thighs back, away from the front of the pelvis.
In a standing position, if you push the thigh bones back while keeping the pelvis stable (push the thigh bones back relative to the pelvis) you push the lower attachment of the psoas backwards causing the psoas to lengthen. You can then focus on stretching the psoas further by reaching the 12th rib upwards.
Standing with your knees pointing forwards, if you roll the thighs inwards slightly so that the inner thigh moves back, you help to lengthen the psoas. Rolling the thighs outwards shortens the distance that the psoas crosses. And so it helps to roll the thighs inwards slightly when stretching psoas. You may be using the adductor magnus muscle in doing so.
In light of the understanding that the psoas major attaches, indirectly to the diaphragm or lower back ribs, you can improve your psoas awareness while standing with this breathing exercise.
Standing with feet hip width and parallel, visualize the back of your kidneys. The bottom of the kidneys are at about the height of the belly button, so focus on the area of your lower back at the height of your belly button and above. Pull the back of your kidneys backwards and upwards, away from your pubic bone as you inhale. Then relax while exhaling.
Instead of focusing on the pubic bone, vary the mediation and focus on either side of the pubic bone. Imagine a straight line joining each of these two points to the same-side kidney.
For even more length, press your thighs back as you pull the back of your kidneys up and back. Relax both while exhaling.
Do both actions smoothly and slowly. Rather than suddenly contracting and relaxing, smoothly contract and relax.
Once you've gotten used to the feeling of lifting (and pulling back) on your lower back ribs, try to keep that feeling while inhaling and exhaling. You can also try to flatten the back of your lumbar spine each time you inhale.