The most important instruction you’ll get in a yoga class may also sound like the most ridiculous one: “Engage your peeing muscles.” “Engage your vaginal walls like you were holding onto a tampon.” “Lift a golden egg from your cervix up behind your belly button.” “Lift your anus up behind your heart.” “Pull your testicles up into your stomach.” “Inner body bright.” “Hug your inner thighs” (to which my student looked at me, looked back at himself, and said, “...but my hands are on the blocks!”).
These are all different ways of saying the same thing: “engage your core.” So why are they so ridiculous? Because it’s extremely hard to describe something that, for many people, is mostly unconscious. We need our cores to sit, stand, or walk upright: we use these muscles so often that it’s difficult to mindfully feel them or engage them at first.
When yoga teachers talk about “the core,” most people assume we mean the rectus abdominis, the “six pack” muscle at the front of your belly. While this muscle is useful in some situations, its action is to shorten the front body and round the spine forward. We cue core engagement to protect the lower back, but repeatedly engaging this muscle alone can actually create lower back problems because it can eliminate the necessary inward curve of the lower back.
Your core is actually much deeper, more subtle (and actually way larger) than this one visible muscle. From the perspective of Tom Myers’ Anatomy Trains, your deep core line begins in the roots of the toes and the arches of the feet, moves through the inner shins and inner thighs, up into the pelvic floor (a suite of muscles at the base of your pelvic bowl that support your pelvic organs and surround your genitals) up into the tranverse abdominis (a corset shaped muscle that squeezes your organs in and up) through your breathing diaphragm, under your ribs and up into your throat and tongue.
The pelvic floor, called Mulabandha or “root lock” in Sanskrit, is key to creating a chain reaction that engages the entire deep core line. This is where all the graphic metaphors come in: a lift in this deep pelvic area makes it much easier to access the tranverse abdominis, which is the abdominal muscle that will lengthen and support the natural inward curve of your lower back.
When I finally figured this out, not only did balancing postures, inversions, and arm balances become much easier, I found that while my inner body seemed to be drawing inward and lifting the way a stocking will if you pull it at both ends, I felt my outer body, including my shoulders, soften and release earthwards. I finally understood Ujjayi breathing: the whispering sound created at the back of the throat is not the goal of this breath, but rather the result of the deep core line engaging up into the throat.
This action is so subtle that yoga teachers have no choice but to use metaphors to try to explain it. Metaphors are the best way of tricking the brain into bringing something unconscious into the conscious mind. My favourite is to imagine a stream of water moving through my centre upwards from the domes of my feet, inner thighs, pelvic floor, and soft palate. Whether it sounds like poetry or nonsense, it works for me. Remember that all these descriptions mean essentially the same thing, so simply find one that works for you. Go forth with your inner body bright, and enjoy your practice!