The pelvic floor in detail

In this article I'm going to turn my attention to an area of the body I've been trying to develop more of an awareness of for quite some years – the pelvic floor (which I have written about before).

The pelvic floor is a multi-layered sheet of muscle and fascia that functions like a hammock at the bottom of your torso. The weight of your organs rest on it and in doing so it helps to maintain optimal intra-abdominal pressure. The muscles work to help maintain continence, and stabilise the hips and the whole spine-leg connection. Once it would've also lifted and wagged your tail! It's also the location of your muladhara chakra.

Over the last year I've been reading and digesting the book "Pelvic Power" by Eric Franklin. It's a very good little book. Franklin specialises in using visualisation to help your awareness and functional coordination of your body, which is great and makes it kinda fun! But as far as I can work out there are a couple of mistakes in his diagrams and I've been left feeling a little confused as to exactly what's what.

No surprise really since the pelvic floor is actually a very complex area!

Bones

Let's start with the bones to get our bearings. Here's an image of your pelvis from the front. If you can feel your hips sticking just underneath your waist, they're your Iliac Crests. The two protrusions sticking down underneath your bum are your Ischial Tuberosities (commonly known as your sitting bones). The two halves of your Ilium come together at the front at the Pubic Symphysis – commonly known as your pubic bone.

Credit: Pearson Education, Inc (2015)

That seems relatively straightforward...

Take a moment to identify the four "corners" of your pelvic floor with your fingers: your pubic bone at the front and your tail bone (coccyx) at the back, and the two sitting bones (ischial tuberosities) underneath. Actually touching these points really helps in getting a sense of where we're at in the body.

Muscles

From now on we have to be careful as there are some differences between the male and female anatomy. I think this is what has confused me for so long, as the books and sources I've read often show what it's like for a woman and don't say how it's different for a man...

(1) The deep layer

So let's start by looking down on the pelvic floor (as per this beautiful image of the female anatomy from BandhaYoga.com). There are three main muscles here: the pubococcygeus and the iliococcygeus (which, together with the puborectalis are collectively called the levator ani – literally "anus-lifter") and the coccygeus.

Credit: BandhaYoga.com

The Pubococcygeus forms the the top layer and connects front to back – tail to pubic bone. To engage this one, visualise drawing your coccyx and pubic bones towards each other. You might even feel some movement in your coccyx as you do this (you're wagging your tail!).

In men, contracting the Pubococcygeus muscle (and/or the abdominal muscles) can voluntarily engage the Cremaster muscle to lift the testicles. Normally the Cremaster is under involuntary control.

The Iliococcygeus and Coccygeus sit underneath and connect the tail bone to the sides of the ilium (a touch back from the pubic bone). The fibres of these muscles form a triangle (or fan) with the apex at the tail bone.

The levator ani muscles can be thought of as a fan radiating out from the coccyx. Engaging and releasing these muscles shorten or lengthen the distance between the hips and the coccyx (putting your tail between your legs). Credit: Eric Franklin

The puborectalis forms a sling around the rectum helping you hold things in when you need to... Squatting when you poo helps relax this muscle and eases the exit channel.

(2) The mid layer

Moving outwards, the next layer is the Urogenital Diaphragm. This is composed of the Deep Transverse Perineal muscle and the Urethral Sphincter (a ring muscle around the urethra – what you wee through).

The word perineum usually refers to the part of the pelvic floor between the anus and vagina/scrotum. The deep transverse perineal muscle sits under the levator ani muscle group and connects side-to-side (sitting bone to sitting bone). It's function is to help support the perineal body (central tendon running north-south along the perineum), the expulsion of semen in males, and squeezing the last drops of urine out for both sexes. To engage it, visualise pulling your sitting bones towards each other. This might take a bit of practice (you can tell when someone is trying by the look on their face...)

This image shows this mid-layer for both the male and female anatomy and how they correspond.

Credit: Antranik

(3) The superficial layer

For this layer it's helpful to look from underneath. As I'm sure you realise, the pelvic diaphragm has a number of holes in it... At the back we have the anus (surrounded by the deep levator ani muscles). At the front we have the urethra (and vagina for women) surrounded by the ischiocavernosus and bulbospongiosus muscles. In men, the bulbospongiosus surrounds the base of the penis and is the big spongy muscle you can feel running front-to-back along your undercarriage. It helps hold an erection and also helps ejaculation. In women, it contributes to clitoral erection, and closes the vagina. For both sexes it contributes to the contractions of orgasm, and also squeezing those last drops of urine out.

Credit: Wikimedia Commons

There's also the Superficial Transverse Perineal muscles which are narrow muscular strips connecting sitting bone to the central tendon on either side. In some people they may be absent or connect slightly differently.

Here's another diagram from Fraklin's book showing the geometry of these muscles on the bottom surface of your pelvic floor (note: diagram is of a female anatomy). There's the triangle at the front formed of the Ischiocavernosus and Transverse Perineal muscles, then the figure of 8 formed by the Bulbospongiosus and anal sphincter. With these shapes, Franklin does a good job in simplifying things to help you work out what's what.

Credit: Eric Franklin

I'd like to finish by noting that these layers of muscle are (of course) all wrapped in fascia, forming the whole connected integrated (and complicated) pelvic diaphragm.

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I am a member of the Zenways sangha led by Zen master Daizan Skinner Roshi, and I teach meditation, mindfulness and yoga at the ZenYoga studio in Camberwell, London. See my website for further details.

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From the ground up: where your roots become your trunk

In this third article in the series looking at how we can best take care of our roots, I'd like to concentrate on the top of our root structure – where our roots turn into our trunk. In the first article we looked at the tips of our roots, our feet, and some of the common problems that arise in that area. In the second article, we looked at the middle section and our knees, focusing on alignment and stability.

As I said previously, I define our roots as everything from the pelvic floor downwards, so here we're going to zoom in and have a look at that very important area – the pelvic floor. It's important both physiologically and energetically in the context of our yoga practice, and it's associated with the practice of Mulabandha (more on that later).

To start off with, let's look at this area physiologially – and for this I've enlisted the help of my sister Kim, a physiotherapist who lives in Stockholm.

In Latin, "pelvis" means basin. The pelvic floor or pelvic diaphragm is composed of muscles and fascia (connective tissue) which span the area of your undercarriage (between your anus and genitals). Physiologically it's function is to provide support for the lower organs (bladder, intestines, the uterus for women) and maintain intra-abdominal pressure (if it wasn't there, each time we took a breath in our organs would slip out between our legs...), to give us control over our bladder and bowel, and to help in child birth (only for women of course). They're also important for sex – for erectile function and ejaculation in men, and for sexual sensation and arousal in women.

The muscles of the pelvic floor are composed basically of three layers or structures. The deepest layer is the pelvic diaphragm (the levator ani), which supports the rectum, and in women the upper two thirds of vagina. The levator ani is actually made of two main muscles, the pubococcygeus and the ileococcygeus. The former is found in the middle, whereas the latter is found along the outer edges of the pelvic floor area. Next there's the urogenital diaphragm. It closes around the urogenital organs supports and has a sphincter-like effect around the vagina in women and contributes to continence. The third structure we find between the anus and the vagina is a structure called the perineal body (or the perineum). This fibromuscular structure is shaped like a pyramid with its base sitting between the genitals and the rectum and its tip pointing upwards.

Image from the book "Mulabandha" by Dr. Kathleen Summers (www.theYogaDr.com)

Back in the 40s, a gynecologist in California called Dr. Kegel started encouraging his patients to practice pelvic floor contractions in order to build up and strengthen the muscles in this area since he thought that would help prevent urinary incontinence and uterine prolapse. Decades of research since has shown that he was onto a winner. So-called "Kegel exercises" are now the first-line therapy for urinary incontinence, primarily resulting from ageing, childbirth, obesity, and the associated straining of chronic constipation. They've also been found to be effective in men undergoing prostate surgery.

So how should we go about finding this complex and rather obscure set of deep musculature? Start off by trying to lift up the whole area by contracting the entire pelvic floor. You’ll feel this as a tightening of the muscles around the anus (as if you are trying to stop a bowel movement), the genitals (as if stopping the urine stream) and the bit in between. This is basically a Kegel exercise.

How did that go? Did you feel a contraction?

If you did, then we can start looking at this in more detail, and try to identify some different structures within the pelvic floor.

First try activating only the muscles you need to stop yourself from peeing – this will be the urogenital diaphragm and the sphincter around the urethra.

Now try activating just the muscles around your anus – you should feel the contraction towards the back of your pelvic floor in the anal sphincter. (Personally I can't do these two separately, but Kim can, and I know others who can too – don't ask me how that came up in conversation though!)  

If you've successfully managed to isolate those two, try activating (contracting, pulling up) the area of the pelvic floor that's between. Now there should be no movement of the anus, the urethra, or the penis/clitoris. What we're finding here is the perineal body and the central portion of the pelvic diaphragm (levator ani) – and can be quite tricky to do. You might need a good bit of time and practice to find this subtle contraction (or it might just work straight away!).

Let me know how you get on using the comment box below.

Next week we'll be looking at why all this physiological detail is necessary for understanding and accessing the more subtle, energetic side of the pelvic floor area. We'll look at why all this is so important in yoga and how it relates to things like the practice of mulabandha (or root lock).