What, exactly, is “the core?”

It’s surprising to me how common the term, “the core”, has become. I hear people talk about it all the time. “I’m going to pilates to work on my core,” or “I think my core is really weak.” But, what exactly is “the core?”

Specifically, “the core” is describing the joints (articulation of two bones), ligaments and muscles that stabilize the rib cage, middle and lower spine, sacrum and pelvic region. When we exercise, “the core” refers primarily to the muscles that control or stabilize this region.

Imagine your trunk, specifically the region from your ribcage to your pubic bone, as a three-dimensional cylinder. If you wrap a large sheet of paper around your trunk, you would have the sides of the cylinder. Then imagine, if you could put a top on the cylinder just under your rib cage and a bottom on the cylinder underneath your sit bones and pubic bone (as if you were sitting on it.) This is the area that is your core.

The core muscles around this region need to co-activiate in order to create and maintain intra-abdominal pressure. That’s seems technical, but mostly what it is saying is that all the muscles in this region that are close to the bones need to work together to create the right amount of pressure to create stability in the trunk. This stability is important because without it your joints and discs are allowed to move too much. Too much movement at any particular joint will create unwanted sheering and will not allow the loads of weight bearing and movement to be transferred between the trunk, pelvis and legs effectively.

Now, imagine you are a long distance runner and every time you move your legs to take a stride, one or two parts of your spine move more than the other parts. In essence, you “give” too much at one or two joints thus creating a lot of friction and sheering at these regions. Over time, these joints will begin to break down, and you may end up with spinal degeneration (i.e. facet syndrome, spinal stenosis, degenerative disc disease).

The primary muscles of your core (that make up the imaginary cylinder) are the pelvic floor (the bottom of the cylinder), the transversus abdominis (the front and sides of the cylinder), the diaphragm (the top of the cylinder), the multifidis (the back of the cylinder) and some of the deep fibers of the psoas muscle.

Learning how to use these muscles correctly during exercise will help develop your core strength and minimize injuries to your spine and pelvis. Cool, huh?

Stay tuned for more information about core stabilization and exercises that help you strengthen it most effectively!