The transversus abdominus muscle (TA) plays a very important role in pelvic floor (PF) rehabilitation and function, but most explanations for controlling continence don't mention any exercises other than kegels.
Why is this? Have our media outlets failed us by over-simplifying the method of PF strengthening, leaving those who are following their direction destined for failure? I believe so. Today lets take a closer look at this postural muscle and the role it plays in core stability and pelvic floor strength.
First let's get a good visual of our anatomy. The muscle fibers of the TA, or lower abdominals, encircle our abdomen and pelvic area, reaching around to the thoracolumbar fascia of our lower back. This area that our TA muscle encircles narrows from our waistline down within our pelvic inlet (the area bordered in the back by our sacrum and on the sides by our 2 pelvic bones.) The transverse fibers of our lower abdominals run around our waist and within our pelvic inlet like a corset or brace that we can cinch up by drawing our belly button in. This corset of transversus muscle fibers narrows like a cone ending at the level of our pubic bone. As our TA contracts, this cone squeezes like a shrink wrap, displacing air and pressure upwards and providing more stability to the individual segments of our lower spine.
I also like to describe this TA squeeze as a vacuum, helping to pull our PF up and our lower abdominals in tight, only to displace the pressure upwards to our expanding lower rib cage and chest. It is easy to recognize someone standing or sitting with the TA muscle engaged because their chest will be lifted making them stand and sit taller.
Now lets focus on role the TA plays in PF strength. It has been shown that the lower fibers of our TA muscle that lay within our pelvic inlet work closely with our PF muscles, which span the base of our pelvis. Some preliminary studies have even shown that there may be a direct connection of some of the fibers of the PF and TA.
Whether or not this is proven to be true - one thing we do know is that these two muscles work together as the deepest contraction, the first stabilizers, as the root of our core.
(You can also include our multifidi muscles in this deep contraction but we will talk about those segmental stabilizers on another day).
You can feel this intimate connection between your pelvic floor and your TA as you perform pelvic floor elevations. When you do a true pelvic floor contraction and elevation, you will begin to feel how your TA is activated every time you work to draw your pelvic floor up into your pelvic outlet.
Conversely, you can also feel your PF contract every time you work to draw your TA in while holding neutral posture.
Studies have shown an increase in contractile force of our TA and PF muscles when activated together vs. contracting individually. This paints a clear picture that we need a strong TA firing along with our PF muscles to achieve optimal strength gains and efficient firing of our pelvic floor. Complete resolution of incontinence or better control of our prolapse symptoms can not be expected if we don't have both these muscles firing together.
Now that we know the importance of our transversus abdominus muscle, how do we strengthen it? The easiest way to identify and begin TA strengthening is in a 4 point kneeling position. Initially as you start, I recommend you be in front of a mirror, positioned so that you have a side view of your belly. To begin, in the 4 point kneeling position, drop your back down to a "flat back position" and relax your belly, allowing it to hang down with the pull of gravity. Form this position, draw your belly up to a tighter position without rounding or lifting your back. The side view you have in the mirror will be great visual feedback as you can see your belly draw up as if you are cinching up your midsection, being careful to maintain your flat back position throughout.
Lifting your belly and holding for a 5 count, 30x each day is a great start to finding and "waking up" your TA.
Once you become aware of your TA you can begin to activate and draw this muscle in tight when you sit down at your computer, when you stand in the grocery line, as you drive your car, etc. I recommend you use a mirror to view the cinching up of your midsection in sitting and standing positions as well to ensure that you are working the right muscles.
Some other helpful tips:
You should be able to continue with a regular breathing pattern while holding your belly in this drawn in position.
You should see no movement of your back when you activate your TA.
If your buns tuck under then you know you have activated your rectus abdominus instead of your TA.
Remember, your belly should draw in with no movement of your low back.
You may feel a tightness in your low back as you contract and hold your TA in.
This is because of the attachment of the TA to the fascia of your low back and the co-contraction of the multifidi muscles of your lower back that also work to hold neutral spine.
Here is a pilates method of discovering your TA
To close this blog, I want to stress the complex rehabilitation of the pelvic floor. "Do your Kegels" should no longer be the very simply message going out to those suffering from incontinence or prolapse symptoms. The truth of the matter is that strengthening our pelvic floor and changing our symptoms requires knowledge of finding and holding your neutral spine in sitting and standing, strengthening of your TA and other coordinating muscles of our abdomen and pelvis, as well as a thorough, 2 part, Kegel contraction.
Continence will come with consistencyTasha Mulligan MPT, ATC, CSCS
Hab It: Pelvic Floor dvd