A Friendly Guide to the Runner’s Pelvic Floor

While pregnancy is often what calls attention to pelvic floor muscles, it’s important for all runners to understand this muscle group. Basically, the pelvic floor is a group of muscles and connective tissue that attach to the pelvis. Together, they act as a sling, or hammock, to support the internal organs of the lower part of the abdomen, including the bladder, uterus, and rectum.

But for runners who have had children or plan to some day, it’s also important to understand how pregnancy affects this part of our anatomy, and the implications of those effects on our running. In addition to supporting our organs the muscles of the pelvic floor are involved with continence, the ability to voluntarily hold in your bodily fluids (read: make it to the bathroom without peeing your shorts).

So let’s explore this muscle system in further detail and learn how it affects your running.

Throw Me a Bone

The many bones of the pelvis.

We’ll start with the bones of the pelvis. You’ve got the left and right ischium, ilium, and pubis. Each ilium attaches to the sacrum and coccyx and each pubis are joined via the pubic symphysis, a cartilaginous joint. Where the ilium meet the sacrum is known as the sacroiliac, or SI joint.

There are many bony prominences (also called ‘bony knobs’ – ew) where the muscles of the pelvis attach, many can be felt through the skin such as the iliac crest, the ischial tuberosity (commonly called the “sit bone”), the anterior superior iliac spine (ASIS), and the posterior superior iliac spine (PSIS).

Pelvis Bones

Ilium (left and right)Upper part of the hipbone.
Ischium (left and right)Base of the pelvis.
Pubis (left and rightInner middle bone of the pelvis.
Large triangular bone at the center of the pelvis, at the base of the spine.
CoccyxThe tailbone.
Pubic SymphasisThe joint where the left and right pubic bones meet.
Iliac Crest (left and right)Wide ridge of bone you feel across your lower back just above your butt.
Ischial Tuberosity (left and right)The sit bones.
ASIS (left and right)The bony knobs you can feel in the front of your waist.
PSIS (left and right)the bony knobs you can feel on your lower back near your belt line.

Put Some Muscle into It

For our purposes, there are two pelvic floor muscles: the coccygeus and the levator ani.

The coccygeus is a triangle shape that connects the lower part of the sacrum to the coccyx. Its primary function is holding up your uterus (so it doesn’t fall out when we run, obvs).

The levator ani is the main pelvic floor muscle and it’s the one that contracts during orgasm (yay!). It is formed by three parts: the puborectalis, pubococcygeus, and the iliococcygeus – try saying that three times fast. You can think of them as the inner, middle and outer parts.

The pubococcygeus, or middle part, is the most important of the three parts of the levator ani. It connects the pubic bone to the coccyx bones, acting like a hammock (it’s at the center of the illustration to the right). This is the part of the levator ani that controls continence; it holds your pee in. This is what benefits from all those Kegels you’re definitely doing all the time.

While the levator ani and the coccygeus are the muscles most commonly thought of in the pelvic floor, it should be noted that the deep lateral hip rotator muscles like the piriformis, work with these two pelvic floor muscles to stabilize the hips.

As we know, each of our muscles is part of an anatomy train and rarely works alone.

Pelvic Floor Muscles

CoccygeusTriangular muscle connecting the sacrum to the coccyx. Primary function is holding in organs.
Levator AniThe sling like muscle that connects the coccyx to the rest of the pelvis. Primary function is orgasm, continence, and holding in organs.

That’s Some Nerve

The major nerve involved with the pelvic floor is the pudendal nerve, which is really fun to say. Poo-den-dahl. The pudendal nerve serves the perineum, the area between the rectum and the genitals, and controls sensation in the genital area (so thank it every day), and provides motor control of the pelvic floor muscles (so your partner should also thank it).

Vaginal delivery of a baby can damage this nerve, leading to problems like incontinence. Additionally, this nerve passes between the piriformis and the coccygeus so if there are any injuries to either one of these muscles, inflammation or prolonged contraction of one of these muscles will compress the nerve. Ouch!

You Can’t Run Away from These Problems

Issues arise from damage to any part of the pelvic floor that can subsequently impact running. Most commonly troublesome are prolapse and urinary incontinence (the peeing of the shorts). Both of these result when muscles lose their ability to contract at full strength, typically because they are over-stretched from childbirth.


Prolapse is when your organs slip or fall out of place, and this is the origin of the myth that running will make your uterus fall out. Prolapse of the uterus is more common in postpartum women than you might think. It should be noted that vaginal birth is not the only cause of weakened pelvic floor muscles and prolapse. Age may also be a culprit, as the natural decrease in estrogen after menopause may cause the uterus to drop. So masters runners take note!

A couple other types of prolapse caused by weakened pelvic floor muscles are rectocele (rectal prolapse) and enterocele (small intestine prolapse). Some female runners who have experienced prolapse describe it as feeling like your organs are going to fall out of your body when you run, sneeze, cough, or do anything. If you experience anything like this, you should definitely see your doctor or physiotherapist ASAP. Prolapse is serious business.

Urinary Incontinence

Urinary incontinence is when you lack voluntary control over urinating. A weakened pelvic floor causes stress incontinence. A small amount of fluid leaks from the bladder, usually because of outside pressure like sneezing, coughing, or even laughing. Stress incontinence can really put a damper on running. It’s no fun to worry about wetting your tights every time you lace up.

Why does it happen? The urine leaks out because the pelvic floor muscles are too weak to fully support the bladder and urethra. Again, it’s worthwhile to see a doctor or physiotherapist who can work with you to strengthen the muscles and minimize the … uh … undesirable effects.

Is prolapse or incontinence normal after having a baby?

Yes! Although they definitely warrant medical attention, these problems are way more common than you may think, so don’t be embarrassed. Although statistics are a little lacking, 40-70% of women in the US experience incontinence after childbirth and it is estimated that nearly half will have some type of prolapse.

You Need Therapy

The dysfunction that stems from the pelvic floor weakness or imbalance is usually a matter of the muscles no longer functioning at full force. This is where seeing a doctor or a physical therapist can be of great benefit, either to give you exercises that help re-strengthen the muscles or offer advice for procedures that might be needed in extreme cases. Look for someone who specializes or is familiar with pelvic floor issues.

A specialist like this can help get you back running faster and healthier. You can find someone in your area here. Additionally, there are many great support sites online to connect with other women who are dealing with pelvic floor problems.

Did you experience pelvic floor issues postpartum?


Bonus Material!

To get a really comprehensive look at the structure of the pelvic floor, check out this excellent 3-D video from Fisio-Notizie

Useful resources:




I'm a licensed massage therapist with a background in biochemistry and also a mother of two. After almost two years of focusing on shorter race distances, I am back on the marathon training horse. My next goal race is the Bank of America Chicago Marathon. I write mostly about health and science as they relate to running as well as being part of a running family.

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  1. This is awesome. I’ve learned so much. Since 2nd kid I’ve had periods of peeing on the run, but it’s not consistent. It’ll be like a week out of the month or when my sciatica flares up. It makes me wonder if it’s a nerve issue – particularly in the latter case. My piriformis tends to knot up when my sciatica flares up so I bet that’s got something to do with it. So interesting!

    1. Exact same thing with me Salty. I tend to notice an increase in the annoying pee factor if my sciatica is flaring up. The only consistency with me is that if my bladder is even remotely filled, there is a 100% chance of me having an accident if I sneeze or cough. Also, if I run in the afternoon, Poise pads have become my best friend. I drink so much water throughout the day that even if I empty my bladder before I go run, I will still leak. And I will leak the whole way through the run.

      1. The pudendal nerve branches from the same root as the sciatic nerve, which passes under the piriformis. Sooo, you are probably right that the issues are related. If your piriformis gets tight or overly spasmy, it will compress down on those nerves. Keep those piriformis muscles loose, ladies.

      2. YES! Afternoon runs are always worse for this problem too. So weird! I read somewhere that when estrogen is low that can cause a slackening of the pelvic floor muscle so that’s probably why it’s worse the week before my period, but it definitely seems related to the sciatica sometimes too. So … another reason to keep up with extrasalt!

        1. Yeah, I caught that correlation between low estrogen and loosening of the PF muscles. It definitely makes sense that you experience your symptoms only at a certain time of your cycle then.

  2. I’ve been waiting for this post!! Of course I want to avoid the trouble of making a PT appt and going to it, but it’s super helpful to know the interconnectedness of all the muscles. I’ll try to pay attention. Also, of course, if I have two cups of coffee, even if I pee right before, it’ll happen during a run. I realized that caffeine can trigger bladder spasms…good post Poppy!

    1. I didn’t know that about caffeine!! I knew it made me need to pee more, but bladder spasms! it makes so much sense!! Won’t stop me from enjoying my daily coffee (when do babies sleep through the night??) but good information anyway. Also, thanks for this really informative post.