Why not to ‘tuck the tailbone’ in a yoga class
A couple of ideas on having a more pelvic-floor-friendly yoga practice.
After feeling some (not normal!) pain last year in my lower back and SI joint, I straightened up in my chair and the pain went away. I started to re-think the common instruction in yoga classes to "tuck your tailbone." When we do this action, more often than not we're straightening the lower lumbar spine as well, taking the curve out of the lower back. To me, it feels that when the lower lumbar spine is straightened and then becomes weight-bearing, it can lead to bulging or herniated discs. This article explores this and other perspectives on tucking and untucking the tailbone.
by Ivana Demmel
It is quite common to hear yoga teachers saying ‘tuck the tailbone under’ when they want to initiate action from the ‘core’ (mulabandha). This might be useful in some cases, working with people who don’t have much awareness of their pelvic floor and the action of tucking the tail can help them access the muscles their brain doesn’t ‘talk to’. But this hint is used way too much and often unnecessarily. Some yoga styles even encourage keeping the tailbone tucked under in most poses for ‘stability’.
The problem is, ‘tuck the tailbone’ could be:
Misleading — Pelvic floor lift in yoga (mulabandha) should come from toning and lifting at the central tendon of the pelvic floor (between the openings) and not from the action of the tailbone. Telling students to tuck the tailbone makes them over-activate wrong muscles — gripping the gluteals, tightening the hamstrings, the deep hip rotators and the very back of the pelvic floor, without lifting the central tendon.
Exposing you to injury — When you curl the tailbone under trying to stabilise the body, tightening your gluteals and the hips together with the rectus abdominis (the ‘six pack’) flattens the lower back. This interferes with the stabilising action of the transversus abdominis (TrA) in front and the lumbar multifidus muscles in the back. The multifidi can’t work properly when the back is flat. This is why a lot of people end up with back pain after classes that focus on ‘core strength’.
Bad for your pelvic floor — keeping the tailbone under we decrease the space between the pubic bone and the tailbone i.e. shorten the pelvic floor. Continuously contracting the pelvic floor while keeping it short will pull the sacrum into the bowl of the pelvis causing your pelvic floor to slack. Doing more ‘strengthening’ work with your tail tucked under will make your pelvic floor even shorter and tighter, but not stronger. Unlike the TrA that (as a purely stabilising muscle) can work for longer periods of time, the pelvic floor should activate only when we need an extra burst of energy and then release to its full length. ‘Keeping it lifted’ = pelvic floor disorders in a long term.
A more pelvic-floor-friendly way to perform mulabandha, would be to keep the pelvis in a neutral position and try to initiate the lift from midway in between the openings without tucking the tailbone.
Keeping the tail untucked we can strengthen and lengthen muscles of the pelvic floor (eccentric contraction) instead of shortening them (concentric contraction).
To be able to identify the right muscle, instead of focusing on action of the tailbone I find it useful to pay attention to action of sitbones, which with the lift of the pelvic floor come closer and with the release slide apart.
There is no need to actively squeeze the sphincters, but just allow the area midway between the openings to gently lift up. I usually say ‘lift from the base of the torso’. This way we can promote the toning action of the pelvic floor, without overdoing it.
The next step could be to use mulabandha only as an exception and instead focus on stabilising the torso from front and back — organically activating TrA and lumbar multifidus muscles as we move. An extra lift from the pelvic floor could be added only when needed to ‘energise the movement’. Dance educator Hubert Godard uses this model to promote a fluid, responsive stability in movement, as opposed to keeping tension in the centre of the body. This could be beautifully applied to the postural practice of yoga too.
We can use use the pelvic lift only as an exception and instead focus on stabilising the torso organically from front and back, keeping fluidity and freedom of movement.
TrA naturally activates as you use Ujjayi breath. Or you can consciously activate it, especially in case of people with lower back injuries or weak abdominals. I like to use ‘draw the hip points towards each other’ to help my students find TrA. Doug Keller uses a nice hint here, saying ‘imagine pulling the drawstring on a pair of sweatpants tighter’. If you on top of it say ‘keep your pelvis neutral’, you can make sure that the lumbar multifidus muscles which protect the discs in the lower back automatically co-contract with TrA completely stabilising the torso.
Your ‘core’ works the best when your spine is in a neutral position. Having the spine in a neutral position means maintaining the natural curves of the spine while having the pelvis in a neutral position — having hip points (ASIS) vertically aligned with the pubic symphysis. So basically, neutral spine = neutral pelvis + ribcage on top + head on top. This way both deep abdominal muscles (TrA) and the deep muscles along the spine (lumbar multifidus) are working to their optimum — balancing the spine and providing enough stability for each movement.
When I say neutral spine I don’t mean maintaining a same static position, but allowing the spinal curvature to come back to neutral as a default, allowing the muscles to relax fully in between contractions. This way the muscles keep their optimal lengths and have enough leverage to generate force to stabilise the body in whatever you are doing.
I personally try to avoid tucking the tailbone hint even in case of working with people who have difficulty in activating their pelvic floor and deep abdominal muscles (e.g. after childbirth). Instead of using action of the tailbone to help in developing awareness of the ‘undercarriage’ I find it useful to make them squeeze a block or a small ball with the thighs while trying to gently tone the lower belly, just above the pubic bone, keeping the pelvis in a neutral position.
Please don’t take me wrong, tucking the tailbone is not bad in itself and please by all means do it as a part of your varied movement diet! But there is really no need to use it as default when practising yoga or living our lives.
by Ivana Demmel