What is Rib Flare?

Rib flare is a term that often gets thrown around in the rehab world and most of the women I see ask me what the heck it means. 🙂 The confusing part is that it can refer to two different things. One is rib positioning, and one is rib angle. So let’s break this down a bit and see if we can make sense of it.

Rib Cage Positioning

This is when your posture affects the positioning of your rib cage. Try it now with me….

  • Really stick out your chest like you’re a kid trying to show someone your belly button.
  • Now, try and hide your chest, like you’re a young girl wanting to hide her breasts.
  • Then, let your hips drift forward and completely relax and sag like you’re a tired mom at the park.
What is rib flare

Do you feel how each body position changes the position of your rib cage?

Sometimes posture is simply a habit of how we hold our body, and sometimes there is tightness or restrictions forcing us into certain positions. There is no such thing as perfect posture, but having the rib cage line up with the pelvis helps the body function a bit better since the diaphragm plays off the pelvic floor and vice versa.

what is rib flare

Think of when an engine belt in a car is “off”. The car will still run, but you get that annoying squeaking noise. If you have less than optimal posture most of the day, your body will start to squeak at you in the form of aches and pain or perhaps diastasis and pelvic floor issues that won’t improve.

The worst thing you can do when trying to improve your posture is going overboard. Trying to hold perfect posture rigidly throughout the day makes the body lock down and creates more dysfunction. Great posture is fluid and variable. So don’t get hung up on one exact positioning, but do focus on what you feel. Where is your body in space? Does it feel good?

Rib Cage Infrasternal Angle

what is rib flare

This type of rib flare is a bit harder to address because it requires changing how muscles fire.

You have little muscles that run between your ribs. These muscles, called internal intercostals, work with the abdominals to produce a forced exhale. I often find that women who have a larger rib cage infrasternal angle postpartum are stuck in a state of inhalation. Meaning, it always looks like they are sucking air in. When we don’t move a part of the body or into a certain position for a while, it can get stiff or stuck in that position. Pregnancy pushes those ribs up and out (into a state of inhalation) to make room for the baby. It often takes a bit of manual pressure and coaxing through specific exhalation exercises to get those ribs back down and in.

Pelvic floor tightness can promote a state of inhalation. Crazy, right, that a little tightness in the pelvic floor can actually decrease the amount the diaphragm expands down, leaving you stuck up?

The diaphragm going down helps to stimulate our vagus nerve which is our chill-out center. It’s no wonder pelvic floor tightness can increase anxiety. The psoas (deep hip flexor muscle) that attaches into the back of the diaphragm has been coined the emotional muscle, probably for a similar reason. If you’re always in a shallow breathing pattern, usually spurred on by paradoxical breathing and ribs being stuck out, then you never release the top of the psoas through great back (not belly) diaphragm expansion. Getting those ribs down and in and getting a great exhale can go a long way for both our physical and emotional state.

I hope this helps explain what rib cage flare or rib cage angle means and gives you a helpful point of reference for reflecting on your posture.


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