Ever feel like your bra feels tighter, or your clothes don’t fit quite right around your waist—despite losing your baby weight? You might be dealing with rib flare.
Rib flare isn’t just about aesthetics; it affects breathing, core strength, posture, and can even contribute to neck, hip, and back pain. So, let’s break it down and understand what’s happening—and more importantly, how to fix it.
What causes rib flare after pregnancy?
Almost all postpartum women experience some degree of rib flare. During pregnancy, your internal organs shift to make space for the growing baby. This causes the rib cage to expand and the pelvis to widen.
After birth, some women’s ribs and pelvis naturally return to their original positions—but for others, they don’t. Genetics, movement patterns, and breathing mechanics all play a role.
The good news? With the right exercises, we can influence the shape and function of the rib cage.
Understanding Rib Cage Positioning
Ribs Flaring Out at the Front
This is often a postural issue.
Ribs Flaring Out to the Sides (Wide ISA)
A flared rib cage prevents full, deep inhalation because the ribs are already in an expanded state. To fix this, we need to work on proper exhalation to encourage the ribs to move fluidly.
Your rib angle (also called the infrasternal angle, or ISA) should change as you breathe:
- Inhale → Ribs expand outward.
- Exhale → Ribs come back in.
If your ISA stays wide or narrow all the time, your breathing mechanics aren’t working optimally.
Rib Flare on One Side?
If one side of your rib cage sticks out more, this is called one-sided rib flare. It’s common (especially on the left) due to how the diaphragm attaches to the spine. But this imbalance can lead to tightness in the neck and back, and even cause pelvic rotation.
The Rib Flare Test
- Lie on your back and relax your abdominals.
- Take a few deep breaths.
- Snap a picture looking down at your ribs.
- Outline your rib angle:
- Optimal ISA = ~90 degrees
- Wide ISA = 110+ degrees
- Narrow ISA = Less than 90 degrees
How to Fix Rib Flare
Step 1: Master the Exhale
If you get a great exhale, then it’s easier to get a good inhale, as it creates more space for movement. So whether you have a wide or narrow ISA, working the exhale can help!
- Wide ISA? Focus on bringing your ribs down and in as you exhale.
- Narrow ISA? Focus on a complete exhale, drawing the front of the ribs in more than the sides.
- Pause at the end of your exhale—this allows your ribs to reset before the next breath.
Step 2: Improve Posture—Without Overcorrecting
Posture isn’t about holding a rigid “perfect” position all day. Instead, aim for rib cage stacked over pelvis, and allow your body to move fluidly through different positions.
- Relax your abs—don’t constantly grip them.
- Remember: What you do all day matters more than 30 minutes of rehab exercises.
Step 3: Improve Rib Mobility
If your ribs and back are stiff, or core muscles are tight, your ribs won’t move as they should.
Here’s what to check:
- Lower back tightness? This can cause excessive arching, leading to rib flare.
- Tight lats? These large back muscles can pull the ribs into an arched position.
- Weak external obliques? These muscles help stabilise your ribs—if they’re inactive (which is common postpartum), your ribs can stay flared.
Step 4: Strengthen Your Core
Your core muscles—including the transverse abdominals (TA)—support the spine, pelvis, and ribs. If these muscles are weak, your rib cage lacks stability, making rib flare worse.
Postpartum, your abdominals have been stretched to accommodate your baby. Strengthening the deep core is key to bringing your ribs back to a more neutral position.
The Bottom Line
Rib flare is common postpartum, but it doesn’t have to be permanent. The right exercises, breathing patterns, and postural habits can help restore function, reduce discomfort, and get you moving (and breathing!) better.
Need help figuring out where to start? Book a session with Roar Physiotherapy and let’s get your ribs moving properly again! 💪🏼
Follow us on Instagram @roar_physio for more tips and expert advice!
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