Breathing seems so simple, right? We do it every day without thinking about it, so surely it can’t be that hard after having a baby?

However, breathing mechanics change dramatically through pregnancy, and for most women we need to work on intentional reconnection to our breath-core-pelvic floor.

During pregnancy, your rib cage flares and rotates outward to make room for a growing uterus. Your diaphragm flattens and loses some of its natural dome shape. Your pelvis tips forward to manage the shifting centre of gravity. All of this is normal and necessary but it also changes the relationship between your ribs, your pelvis, and your diaphragm, which is the foundation of how you breathe, brace, and manage pressure through your torso.

Postpartum, many women are left with a rib cage that’s still flared, a diaphragm that isn’t moving through its full range, and a pelvis that isn’t stacked underneath the ribs the way it needs to be. Everything that depends on efficient breathing (pressure management, core coordination, pelvic floor function) is working from a weaker foundation.

This is why just doing more core exercises doesn’t “fix it”. Reconnection and coordination have to come first — teaching the ribs, diaphragm, and pelvis to move together again —before more demanding core work will actually transfer into function.

Are you finding yourself doing endless breathing drills but struggling to progress? Here are 3 simple ways to rebuild that coordination.

1. Add a Reach

One of the most useful ways to improve breathing mechanics postpartum is to add a reachinto positions you’re already working in.

Serratus anterior is attached along the ribs, so when your shoulder blade is fixed in place,this muscle can actually help move the ribs — which makes it a genuine player in breathingmechanics, not just a shoulder”muscle. Its fibres also intertwine with your externalobliques, so a well-functioning serratus gives your obliques more to work with. An activereach through serratus is one of the simplest ways to switch that connection back on.

Reaching also gives you a tool for shaping the rib cage depending on what it needs. Reachas you inhale and you widen a narrow rib cage — helpful if you’re working with a lower diastasis recti or pelvic floor dysfunction. Reach as you exhale and serratus helps closethe front of the ribs, more useful if you’re healing an upper or middle diastasis recti.

Actively bringing the scapula forward to close the front of the ribs also opens the back ofthe rib cage and the muscles between the shoulder blades, so holding that position on aninhale can direct more expansion into the back and ease stiffness there.

There’s a postural piece too. Being able to achieve upward rotation of the scapula,separate from rib cage movement, means you can reach overhead or push forward withoutcompensating by arching your back and flaring your ribs, or rounding your shoulders anddropping your chest. That disassociation is what allows reaching to improve core control,posture, and breathing mechanics together — rather than the ribs and shoulders justmoving as one block.

Adding a reach into a static hold or a controlled movement gives you a way to cue all of thiswithout needing to consciously think about your ribs at all — the reach does the work foryou. Some ideas:

Wall sit with reach Set up in a shallow quarter squat, stacking your body against the wall, thenreach horizontally or low (option to add a yoga block between the knees). The reach draws theribs down out of extension while the stacked position keeps the pelvis underneath, encouraging abreath that has room to expand into the back and sides of the rib cage rather than the front only

Short lever side plank with reach Challenges lateral core control on one side while the top-arm reach lengthens and anchors the ribs— helping you find rib mobility independently on each side of the body, rather than relying on symmetrical bracing.

Glute bridge with reach + iso adductors This pairs a glute contraction with a serratus reach through the upper body, so you’re not just isolating the glutes — you’re integrating breath, rib position, and upper body control into the same rep. Reaching over your chest against resistance while your ribs are moving requires a controlled exhale and some genuine rib mobility, which is exactly what most postpartum bodies need to relearn. It’s a small addition that makes a big difference in how the whole system works together

2. Get Your Ribs Stacked Over Your Pelvis

Position matters as much as effort when it comes to diaphragm function. The diaphragm works best as a dome, moving down and out on the inhale and recoiling up on the exhale. That movement depends on the rib cage sitting directly over the pelvis, not flared forward or tipped out of alignment with it.

This is where the diaphragm, deep core, and pelvic floor become one connected system. Think of the torso as a canister: diaphragm as the lid, pelvic floor as the base, deep abdominals and back muscles as the walls. On an inhale, the diaphragm descends, the canister pressurises, and the pelvic floor lengthens to accept that pressure. On the exhale, the diaphragm recoils up and the pelvic floor and deep core help manage the pressure back out. This is intra-abdominal pressure management and it’s happening with every single breath, whether you’re thinking about it or not.

That system only works properly when the canister is actually stacked — ribs over pelvis, not shifted forward or tipped out of line. When the ribs sit ahead of the pelvis, which is common postpartum and often reinforced by fatigue, feeding positions, and carrying a baby, the lid and base of the canister are no longer facing each other. Pressure doesn’t distribute evenly through the deep core and pelvic floor and instead it tends to leak out through the path of least resistance, which is often exactly where you don’t want it: down through the pelvic floor, or forward through a healing diastasis.

This is also why bracing cues alone don’t solve pressure management problems. You can’tbrace your way out of a positioning issue. If the canister isn’t stacked, no amount ofengaging will get pressure to move through the system the way it should. The alignmenthas to come first.

90/90 positions are one of the most effective ways to practice this stack, because theytake standing posture and gravity’s usual demands out of the equation and let you feel therib-pelvis relationship and the pressure shifts that come with it directly. Examples:

90/90 breathing with KB reach The kettlebell reach guides the ribs into a stacked positionover the pelvis while you breathe, giving immediate feedback on whether the ribs arestaying down and connected through the exhale rather than flaring back up.

90/90 hip lift with reach Adds a small pelvic lift to the stacked position, asking the pelvis to move while the rib cage holds its position — building the coordination needed for the ribs and pelvis to work together. This variation also recruits the proximal hamstring to help bring the pelvis into better alignment: the key is a small pelvic tuck, lifting the sitz bones just off the floor, with a hamstring drag along the wall.

3. Add Rotation

Once reach and rib-pelvis positioning are in place, rotation adds the final piece: getting theribs moving and expanding through a fuller range.

The diaphragm doesn’t just move up and down — its fibres attach around the entire inner circumference of the lower rib cage, and each side can move somewhat independently of the other. Rotation through the thoracic spine takes advantage of this. As the rib cage rotates, one side of the diaphragm and rib cage lengthens while the other shortens, which is exactly the kind of asymmetrical mobility a full, three-dimensional breath depends on. If the thoracic spine and rib cage are stiff or stuck moving as one block, the diaphragm is forced to work through a smaller, flatter range on every single breath, no matter how good your rib pelvis positioning or reach mechanics are.

This is also where postpartum stiffness tends to show up. Time spent feeding, carrying, and hunched over a car seat or cribs pulls the thoracic spine into flexion and keeps it there, which limits rotation and, with it, the space available for the diaphragm to expand into. Rotational work restores that mobility so the rib cage has somewhere to go on an inhale, rather than the breath getting stuck trying to expand a rib cage that can’t move.

Rotational breathing work challenges the diaphragm and intercostal muscles to expand and contract asymmetrically, which is how the rib cage actually needs to move day to day— reaching for something, turning to check on a baby, rolling over in bed. Static, symmetrical bracing doesn’t prepare you for any of that.

Thoracic rotation — forearm down Isolates rotation through the upper back and rib cage while keeping the lower body stable, building rib mobility that’s specific to the thoracic spine rather than compensating through the lumbar spine.

Thread the needle with breath Pairs rotation with an exhale through the movement, reinforcing that ribs should move and expand asymmetrically with breath rather than staying braced and still.

The Bigger Picture

The goal of these 3 approaches is about restoring the coordination between your ribs, diaphragm, and pelvis that pregnancy and early postpartum naturally disrupt — so that when you do return to more demanding core and full body strength work, it’s built on a foundation that can actually manage pressure well.

This reconnection work is exactly where the Return to Strength program starts. It’s built to rebuild breath mechanics, core coordination and pelvic floor function step by step, before progressing you into heavier strength training — so you’re not skipping the foundation to get back to the gym.

Start your 7-day free trial of Return to Strength today!