WHAT IS THE CORE?
When people talk about “the core”, they are typically referring to the entire midsection of the body – a cylinder-‐shaped region with the diaphragm (in the middle of the ribcage) as top, pelvic floor muscles (at the bottom of the pelvis, attaching to the tailbone and the sit bones) as bottom, and all the muscles, ligaments, bones, organs, etc in between. Similarly, when people talk about “the core muscles”, they are not just referring to the abdominal muscles –29 muscles work together to stabilize the body’s core, and these muscles are all considered “core muscles”.
The core houses the body’s centre of gravity, so controlling this section of the body is important for controlling posture, balance, and movement. The muscles of the core work together to serve 3 important functions:
1. Facilitating healthy breathing,
2. Supporting healthy posture in sitting and standing, and
3. Enabling stable movement of the limbs and the body through space (during walking, bending, etc).
Although we often talk about improving “core stability” in the exercise world, this term can be misleading – rather than promoting rigid, continuous engagement of the core muscles, what we mean to encourage is a healthy connection between the nervous system and the core muscles, enabling the core muscles to respond appropriately to the demands of everyday life. Healthy core muscles automatically kick in to stabilize the body as we lean over a table to retrieve a cup of coffee (and then they help us keep from spilling it as we straighten up). They also stabilize the body in preparation for lifting a heavy item like a child or a piece of furniture – and importantly, after becoming more active to help us perform these tasks, they reduce their activity again when we wish to rest rather than remaining tense. The type of stability provided by healthy core muscles is said to be “dynamic”, meaning that even while stabilizing our trunk during physically demanding tasks, their activity fluctuates like a piston, enabling us to breathe efficiently while we move.
Unfortunately, this healthy connection between the nervous system and the core muscles can be diminished by interference from chronic pain signals, or chronic underuse of the core muscles (which is common, since many of us spend our days sitting). Over time, a reduced ability to appropriately activate the core muscles can lead to poor posture, inefficient breathing, and excessive or uneven pressure/strain on structures like discs, bones, and ligaments. The good news is that connections between the nervous system and the muscles can be improved through “neuromuscular re-‐education” – regular, proper practice of the skills one wishes to improve, such as using the core muscles to achieve and maintain good posture, using the core muscles to stabilize the body while moving, and breathing efficiently during movement.