Have you ever wondered how you can fart without pooping your pants?  Well if you haven't before this moment...now you have, and yes, you're welcome :). 

Hi everyone! It's me, Dr. Kelly, your favorite internet Pelvic Physical Therapist, here to teach you incredible facts you never knew, you never knew, about your down there.  Today's fun lesson is about the Rectoanal Inhibitory Reflex, or, as we call it in the biz, "the RAIR" (pronounced "rare", preferably with a slight growl like you are a sassy kitten ❤️)

The Rectoanal Inhibitory Reflex (RAIR) is one of my favorite things about the rectum.  It's also the root cause of MANY of my clients' chronic constipation, then prolapse and later pee frequency and incontinence problems, so this post is one that I am PASSIONATE about bringing to life.  

Friend, I know you have so many questions....like
- "What is the Rectoanal Inhibitory Reflex?"  
- "How Does it Help Me Fart?"  
- "How is It Causing My Chronic Constipation?"  
- "How do you talk about poop SO MUCH, and yet stay so happy?"

Friend, I have answers to all of these questions...and more...so let's get to it :) 

What Is the Rectoanal Inhibitory Reflex

The Rectoanal Inhititory Reflex (RAIR) is an amazing adaptation that our body developed, in order to attempt to time poops to "convenient" times.  

First, please know that our pelvic floor muscles act like an elevator in a four story building at the bottom of our pelvis.  These muscles are meant to live on the ground floor....and be called into action to the 1st, 2nd, 3rd and 4th floors during the day...but always relax back to the ground floor at rest.  In some activities, like a deep squat, they even need to elongate to the subbasement, and sometimes, like if we are carrying a child, or lifting a dumbbell or barbell the muscles need to be eliciting tension WHILE ELONGATING, which is SUPER BOSS of them, those baddies.  If you can comprehend this, even a tiny bit, you already understand more than 90% of most humans.  (And if you can't, don't fret, I explain more later--keep reading).

The RAIR at it's best: Letting us Fart without pooping our pants

A good fart is the RAIR at its absolute best.  

Your sweet pelvic floor is behaving ideally. It is resting at the ground floor, and you are working at your desk, or playing with your kids.  

Your internal anal sphincter muscles are constantly sampling what's inside the rectum (the holding space for the poop before it comes out), to see what's in there...and they are suddenly sensing a bit of solid poop (not enough to have a bowel movement yet, though) AND some air....

...no worries, though....they cause a subconscious (automatic) contraction of your pelvic floor muscles to the 2nd floor, which is held for a little while (let's say 10 seconds or so), which causes a SECOND automatic reflexive BACKWARD MOVEMENT OF THE LARGE INTESTINE TO MOVE THE POOP BACKWARDS UP THE TUBE, JUST A TOUCH, away from the butthole.  When these same magical cells sense this has happened, they relax once back to the ground floor, then a second time to the subbasement, to let the air out (but not the poop, because they have masterfully moved it backwards away from the opening, those jugglers!).  At this balance point, you let out a small fart (hopefully quiet and not too deadly), after which the solid poop drops back to where it belongs, until it gathers enough volume (size) for the sampling cells to report to you that you need to go #2.  

FASCINATING, isn't it?!?!?  

The reflex is SO AWESOME!!  It doesn't always work with liquid, however, which is why "the urge" you get to go, when you have diarrhea is SO MUCH MORE URGENT than a solid poop. Your body completely understands that there will be no passing of gas without passing of poop, so it wants to send a clear message to you to get your cute butt to the 🚽, ASAP. 

So that's what I LOVE about the RAIR, and now you can ask your friends, "do YOU ever wonder how your butthole knows if it has to fart, poop, or RUN to the bathroom?" then wow them with your knowledge of the internal anal sphincter, sampling and RAIR.  

Let's move onto talk about when I don't love the RAIR---when it can cause MAJOR problems...

The RAIR at its WORST: HOW Your Overactive Pelvic Floor is Making You Constipated (really)

To understand this problem, we need to now understand that the pelvic floor muscles are surrounding VERY INTIMATE areas...areas that are related to reproduction and elimination of waste...these areas are VERY VITAL to the survival of our species.  And for that reason, the pelvic floor is hard-wired to the emotional center of our brain, the amygdala, via the vagal nerve. 

Now let's connect the dots.  Because of this integral connection, if a human experiences pain or stress, their pelvic floor will enter "high alert state", ("fight or flight"), and the pelvic floor will automatically engage up to the 2nd or 3rd floors.  This pretensions the pelvis, stiffening it to help us be ready to run away from the tiger that wants to eat us.  

From a digestion perspective, though...if the pelvic floor is above that 2nd/3rd floor for longer than 10-seconds, the RAIR is activated, right?  RIGHT.  And we didn't even mention that your body's natural reaction to ANY back or hip pain is ALSO to overtigthen the pelvic floor muscles (AND reduce the support of the deep abs, back and butt--THANKS, brain!)...which further activates this RAIR.

So what happens if your Rectoanal Inhibitory Reflex, which is essentially the brakes on your poop-making system, have been on, for days, months, years on end?!?!?!  

 The RAIR is an Internal "Brakes On" Signal to Many People's Digestive Systems, and They Don't Even Know It

If your life is presently really stressful, or  is full of pain, or has been full of pain in the past, the chance is nearly 100% that your pelvic floor muscles are resting in a state of hypertonicity. And that means that your RAIR is activated "all the time."  

Translation: yoru pelvic floor is telling your brain, and your colon, that it is "never a safe time", "never a good time" to have a poop...and therefore the colon is not moving poop through the tubes effectively.  

And that's a problem, friend. 

Even if you drink "enough water" (which you might not, because you're stressed or in pain--but the answer is half your body weight in pounds...in fluid ounces...so if I weigh 160#, I should aim for 80 fluid ounces of intake every day). 

Even if you eat enough "fiber", you still might not poop, and especially if you eat enough fiber but don't get enough water AND your pelvic floor is hypertonic...YOU ARE GOING TO BE CONSTIPATED!!!! 

Lucky for you (& your pelvic floor), there is an EASY solution to this chronic constipation!

Yes, the easy solution to this chronic constipation is connecting to, then relaxing your pelvic floor, THEN learning to keep it relaxed WHILE engaging OTHER MUSCLES for daily tasks.  Pelvic Floored programs are one of THE ONLY Physical Therapy and Pelvic Floor Exercise Programs out there to have the confidence and audacity to each you this foundational topic thoroughly and effectively.  

We do this by utilizing the AMAZING tool, The Cooch Ball, invented by the incredible Jana Danielson.  This tool requires no internal work, and I have found it to be a GAME CHANGER for client adherence to home programs and foundational understanding of pelvic floor coordination patterns. In just 3-5 minutes a day, you'll begin to connect to your Pelvic Floor Muscles for the first time in your life!!!

While you learn to connect to your muscles, and relax them, you are working on improving your hydration and nutrition habits, as well as movement habits.  

Once you have the foundational "Big 3" movements in place, then we provide you with a framework or ladder to ascend at your own pace  where you master one level of coordination tasks, then the next, and the next, until you achieve your desired goals. 

With this program, Pelvic Floored is proud to boast a >90% success rate of resolution of incontinence and prolapse symptom complaints, which is significantly above average.  Check out Dr. Kelly's Treasure Chest, where as of October 2025, all online courses are now accessible (except for the professional facing course) for one low monthly subscription fee.  

But I did digress there a bit, Back to how relaxing the Pelvic Floor Reverses the RAIR!!!

Oops, sorry--I do get excited :) It happens in person, too. So once we get you to find and RELAX the pelvic floor, for which you REALLY do need something like the Cooch Ball, or a Physical Therapist's treating hands on your pelvic floor, to do, the pelvic floor can come down below the 2nd floor, and the RAIR is finally not activated.  

BUT...if the colon has "been used" to going slowly for days, months, or years---you now have a bit MORE work to do to help it get moving.  You also need to move the spine, and the abdominal tissues.  As we mentioned, you need to give your body enough fluid and the right kinds of fiber and fuel to make the poop, AND, importantly, you need to make sure you are coordinating your pelvic floor well enough to "not accidentally" re-activate the RAIR during your daily activities, which DOES happen sometimes.  

Finally, when you are sitting on the toilet, it's important to remember to relax the pelvic floor, and allow the colon to push the poop out.  There is a special movement called "bearing down" that should come COMPLETELY from the pelvic floor and NOT the stomach.  This movement sends our pelvic floor muscle-elevator from the "ground floor" position in our 4-story building into the sub-basement very gently for a few seconds, which is the GO signal for the colon.  It takes some practice to master, but I promise you'll be able to figure it out if you practice.  You just need to get your muscles off the roof of the building first :).

Okay--that was a meaty post!  I've been meaning to write it for a while, so am THRILLED to bring it to light!  Comment below if this helped you understand your constipation better, and please share with friends and family if you don't mind!!   

Until next time,

XOXO

Dr. Kelly 💋

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