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.