core stability from the inside out
Updated: Apr 2
My understanding of core work has changed over the years, but for a long time, I understood it as primarily a need to “strengthen the abdominals” in order to “support the back.” In order to accomplish this, I had my students do supine core work with their lower back “glued” the floor; I instructed them to “hollow the belly” and to “pull their belly-button toward the spine.” Along the way, I began to hear more about “bracing” vs. “hollowing,” but it wasn’t until I really came to understand the anatomy of the diaphragm and experienced intra-abdominal pressure for myself that the lightbulb clicked on in my brain. I had a feeling of being supported in my lower abdomen and back that felt completely natural. I stopped sucking in my tummy all the time, and my instagram pics looked less svelte, but my kettlebell swings improved and I care a lot more about that.
There are some incredible resources out there for you to read about this topic, but since you made it to my page, I’ll give you a really simple overview to get you started, and then you can decide if you want to read more or try it for yourself.
meet your diaphragm
This picture illustrates the dome-like shape of the diaphragm, tucked neatly away below the heart and lungs. As you breathe in, the diaphragm drops slightly down; the lungs expand. As you breathe out, the diaphragm lifts back up; the lungs contract. You can watch a video of this here. Try breathing along with the video and see if you can imagine or sense this movement in your body.
While I’m sure you knew that the diaphragm was used for breathing, you may not have known that the diaphragm is also a postural stability muscle. Remember the last time you got really winded? You probably bent over and rested elbows or hands on your knees, or had to sit down. That’s because the diaphragm was working so hard it was no longer able to help hold you up.
Intra-Abdominal Pressure: The Inner Core
When all is going well and you’re able to breathe “optimally” (more on that in a minute), our inhale causes the diaphragm to drop down, increasing intra-abdominal pressure (IAP). Think for a moment of the air in your tires. When the tires are not fully inflated, they aren’t as stable or strong, right? No matter what the outside of the tire is made of, it’s not going to be very useful if it’s only half-inflated. The same is true with our inner core. If we are not stabilizing or pressurizing from the inside-out, all of the core exercises in the world are not going to make us as strong or stable as we’d like.
This is why hollowing, or “pulling the navel to the spine” is not terribly useful.
How Should We Be Breathing?
There’s no one “right way” to breathe. As we move around and respond to stimuli, our breathing naturally changes. Our breathing patterns are complex, and highly attuned to our nervous system.
All other things being equal, if we are in a calm, relaxed state, and our airways are clear, an inhale will allow the belly, sides, and low back to expand evenly as the diaphragm descends. We should also have expansion through the ribs, and into the upper chest, without strain in the neck (or other accessory areas).
Now, if we are experiencing a stress response, it is normal for the breath to become shallow and quick; In this case, the accessory muscles of breathing (scalenes, trapezius, sternocleidomastoid, pec major) work to lift the ribs, increasing the air that is taken in. For trauma survivors, or those of us living through prolonged stress, this style of breathing may have become second-nature. In these cases, you may not be able to get the diaphragm to move enough to experience that expansion. First, we would want to get you out of that stress response and into your window of capacity.
Want to Try it Out?
If you are feeling relatively un-stressed, you can give this a try. If you are not too relaxed, go dance around, throw a ball with a friend or a dog, or get yourself feeling a little more at ease, first.
Now: Lie down with your knees bent, soles of the feet on the floor. Bring your hands to your bottom ribs, so that your fingers are resting partially on your ribs and partially on your abdomen. Wrap your hands around the side waist so that your thumbs are moving toward your back.
Breathe in here, and see if you can feel a gentle expansion of the ribs, belly, side waist, and back. It’s important to see if you can find it in all of these places and not just the front (which can indicate that you’re simply hinging from the rib-cage and not truly expanding the diaphragm). You will feel it more easily in some places than others. That’s normal. With time and practice, this gets much easier.
“Brace Yourself!” and Movement
Once you’re able to breathe in this way lying down with knees bent, you can try it in other positions. Straightening both legs will be harder; sitting up, harder still. Eventually, you’ll be able to breathe naturally in this way while you’re standing and even during movement.
Abdominal bracing is a gentle pressurization from the inside out that supports us in a natural way. It is not a hardening or gripping of the lower abdominals. This type of engagement is counter-productive; it keeps the diaphragm from being able to descend.
If you have patterns of tension, trauma, or anxiety, be patient with yourself as you begin this work, especially if it feels painful, unpleasant or frightening. Many times the tension that we are holding there, or the breathing pattern we’re using, is helping to “hold ourselves together,” literally and figuratively. In my work with clients, I often find that this can take time and patience.
Resources:
Jennifer Snowdon, Integrative Breathing Therapist- she offers regular breath retraining workshops and is a trauma-responsible practitioner
Aaron Swanson, PT, DPT: Breathing – Part I – Anatomy & Mechanics & Breathing – Part II – Indications, Assessment, & Intervention
Hans Lindgren, DC, DNS Practitioner: Core stability from the inside out, Diaphragm function for core stability