Wendy Powell

Working Your Core Correctly | Stick your Butt Out!

curved line

Should your ‘tuck your tailbone’ to work your core? No. Here’s why.

Here’s some stuff you may have been told as a kid in ballet class, or just last week by an exercise instructor… cues we have been hearing (and as instructors, taught to teach) for years about how to stand in ‘correct posture’ or how to ‘work your core’:

“Squeeze your butt”

“Suck in your stomach”

“Tuck your tailbone under”

If you’re following these kind of cues, then unfortunately you’re building yourself a fairly flat shaped backside, possible pelvic floor weakness and maybe ‘weak knees’.

Progressive programs like MUTU System don’t tell you to do that stuff… so you get the best workouts for your body!

Here’s a little ‘am I engaging TVA correctly?’ challenge for you instead – stand side on to that mirror, I want you to ‘engage your core’ WITHOUT moving your pelvis. It’s harder right?

Because ‘engage your core’ doesn’t mean, ‘suck your stomach in’ and it definitely doesn’t mean ‘tuck your tail bone under’ or squeeze your butt. It means drawing your belly button back VERY GENTLY (this really is a very subtle movement, not a forceful one – if you’re not sure, draw it back, then halve that), or imagining a line between your hip bones that you’re going to draw together… (yes, you should feel your pelvic floor lift when you do this – that’s good!)

Try not to let your pelvis tuck under. Breathe out, slow and steady and draw your belly button in…. but keep that natural curvature in your spine. It’ll feel at first like you’re consciously sticking your backside out.

Try it with a ball behind you – keep your butt curved to the ball!

Try it kneeling astride a large cushion or bolster, sitting on the front of a chair or on a fitball: Sit on your sit bones, upright (not on your sacrum with a curved back) and then try to very gently engage your TVA muscle, without tilting your pelvis and rolling onto your tailbone. Also try squatting from standing but supporting your back with a ball behind you, as in the picture.

You see there is a difference between ‘finding your core and ‘working your core’.  If you haven’t found it, you can’t work it. Our brain forgets how to talk to some muscles in our body after pregnancy and childbirth because they have been unused, in a position not be able to work optimally, or taking up the strain of other imbalances and… your body cannot use a muscle that your brain’s stopped talking to.

Tucking your pelvis under and/or squeezing your butt shortens the pelvic floor muscles. If you can visualise, your pelvic floor muscles are a hammock of musculature attached at your tailbone at the back and your pelvic bone at the front. So curling your pelvis underneath you shortens and tightens the muscle by bring your sacrum / tailbone closer to your pelvic bone.

This movement has 2 downsides:

  • A tight muscle is not a strong muscle – your pelvic floor needs to be supple and strong, able to work in its full range (or length). Pelvic floor exercise should be a synchronized  ‘lifting’ effort of all of your deep core muscles working together, not an isolated squeeze, and tucking your tail under keeps it permanently short and tight.
  • Your TVA cannot work correctly if your pelvis is tucked under. Similarly, your TVA does not create this movement. So being in the tucked position is doing nothing for your core muscles.

So squeezing and tucking is not helping your pelvic floor, and its not helping your core.

Try squatting, and watch yourself side on to that mirror again – your tailbone should head down and back, sure (don’t over arch your back and stick it up)… but not under. Watch yourself and try to maintain that natural curve of your spine as you squat. Aim to have your shins stay vertical, and use support if you feel unstable at all. Holding onto something solid like a stair rail or heavy table (or hold onto someone) with both arms in front of you is an effective support, to be able to focus on form rather than falling over!

There are of course many natural and valid ways to squat, and a full, deep resting squat position or an Olympic lifting squat for example will not necessarily involve vertical shins or an entirely neutral spine. But the above pointers are for you to develop a safe, effective squat that will serve you in an exercising squat, and as you go about picking up things, lifting things and general movement. As your squat, your core and your glutes develop in functionality, response and strength, by all means experiment further!

So there you have some Butt Homework to be going along with as you start working towards a flat tummy and a perky butt, not the other way round.

Are you following a program that tells you to tuck your pelvis under? Are you an instructor who uses this cue? I’d love to hear what you think!

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