If yoga were rock and roll, then the phrase “engage the core” would be the equivalent of Bohemian Rhapsody. Everyone’s heard it, but few actually know what it really means. Nevertheless, core engagement is a huge component of balance, stability, and safe movement. So let’s take a second to break it down.
Types of Muscle in the Core
Firstly, core muscles can broadly be sorted into two functions – stabilization and movement. Many muscles such as the psoas provide both these functions depending on the movement being performed. The stabilizer function provides structure that allows for movement and weight bearing, while protecting the spinal cord. It also allows us to balance by giving us control over our weight distribution across any given balance point. For example, in a handstand without a stable core, the legs and hips will flop over and behind the shoulders making it impossible to maintain. With the core engaged, the weight distribution remains constant and stable.
Movers, in turn, are primarily responsible for creating movement by activating joints. While strengthening movers is fairly straight-forward, it's often more difficult to think about strengthening muscles that primarily provide stability since we’re often less conscious (or in control) of their activation. But before we talk about strengthening, let’s briefly overview just a few of the muscles in the core to understand the number of components in play.
Some main stabilizers in the core are…
The transverse abdominis – exists in the layer below the oblique muscle and functions almost like a corset (providing compression) around the abdomen. Can be engaged by drawing the belly button towards the spine.
Obliques (internal and external) – two layers of muscle on the sides of the abdomen that provide compression to the trunk when flexed on both sides, or rotation of the trunk when flexed on one side.
Pelvic floor muscles – series of muscles spanning the bottom of the pelvis providing support to the bladder, bowel, and uterus.
Diaphragm – thin layer of muscle separating the stomach from the base of the chest.
Lumbar multifidus – series of muscles attached to and supporting the spinal column.
Transverspinalis – provide rotation and extension to the vertebral column along the back.
Some main movers in the core are…
Psoas (major and minor) – lying deep against the posterior abdominal wall, the psoas serves a similar function to the hip flexor while also providing stability and strength at the base of the spine. This helps the lumbar spine maintain its normal curvature.
Rectus abdominis – these are our “6-pack” muscles that assist in trunk flexion (i.e. curling up from the back).
Erector spinae – back muscles that assist in trunk extension (i.e. standing up straight from a bent position).
Latissimus dorsi – extends from armpits to lower vertebrae along lower back. Responsible for multiple movements of the shoulder joint.
Hip adductors and abductors – groups of muscles that move the legs away (adduction) and towards (abduction) the body’s center line.
So how do you actually engage the core?
With all that said, how exactly are we supposed to figure out which we’re supposed to engage? Furthermore, how can we strengthen stabilizers, that we’re not even fully aware of?
Firstly, we need to bring awareness to our different mechanisms for core stabilization, particularly the deeper layers of muscle. Start with the transverse abdominis muscles by pulling the navel in towards the spine. This should also allow you to feel a lift in the pelvic floor muscles.
Go ahead, give it a try.
Then begin to feel the contracting in your internal obliques on the side body. At this point, you’ll most likely be able to notice the difference in stability. Now draw your attention to your tailbone. Is it tucked under (posterior pelvic tilt)? If so, you’re most likely engaging the rectus abdominis rather than your deeper stabilizers. While this type of tilt can be protective in certain postures, it won’t always help you strengthen your core since it actually takes tension off your transverse abdominis and prevents your pelvic floor muscles from working in their full range.
From here, the next step is to move. Luckily, yoga is one of the best ways to strengthen stabilizers because of how it shifts weight onto different parts of the body. When in uneven postures (where weight is bearing more on one side of the body than the other) stabilizers will engage to redistribute the existing tension. Similarly, with any balancing posture, stabilizer muscles are working hard to keep us upright.
When we’re unable to effectively activate our stabilizers (such as those in the core) we risk disproportionately bearing weight in areas that can cause injury. For example, if we enter a handstand without learning to engage stabilizers in the shoulders, we’re likely to injure our shoulder joints, or if we perform planks or chaturanga without engaging the core we may end up compressing our lower back.
While the core is complex, core engagement (and the engagement of any stabilizer muscles) isn’t difficult to achieve. All you need is a little practice and awareness. By thinking about how weight is distributed and where stability is needed to allow for movement in other areas, we can also avoid significant injury.