How to Permanently Fix an Uneven Chest (It's Not What You Think)
You clicked on this because you noticed one side of your chest is smaller than the other. I dealt with this for years — along with debilitating shoulder pain — and it left my body looking a little funky and my training completely stuck.
I tried everything to fix it across five-plus years. Scap retraction drills, I's Y's and T's, Bosu ball push-ups, a ridiculous amount of unilateral presses, bands, machine work — anything I could do to wake up that smaller pec. None of it helped. If anything, it made things worse. And I continued to obsess and spiral year after year.
A lot of people will tell you the cause is weak versus tight muscles, poor posture, a bad push-to-pull ratio, or even organ asymmetries and postural patterns you're stuck in. And while some of that can play a role, in my experience, the answer is way more simple than you're being told.
I walk through the full test, mobility drills, and loading progression in the video above.
The Real Reason One Pec Won't Grow
Most advice about uneven pecs skips the most simple yet critical step: checking if your shoulder can even move through the range you're trying to load.
In 99% of the uneven chest cases I've seen — including my own — the smaller pec is attached to the shoulder that can't extend properly. And if your shoulder can't extend well, your pec can't stretch eccentrically and load through a full range of motion. We all know the eccentric portion of a lift is the most important part when it comes to building muscle. It doesn't matter how many single-arm dumbbell presses you do — if you don't have the mobility, you're not going to load that muscle properly.
What ends up happening instead is compensation. Your shoulder hikes up, working the upper trap. You push your elbow out wide, putting more stress through the joint. Or you rotate your entire rib cage in the direction of the limited shoulder. Think about people who bench and the bar tilts every time they press.
After five-plus years of seeing physical therapists, chiros, and posture specialists, not a single one ever tested shoulder extension on me. It was maddening. But once I saw how limited my shoulder extension was and then improved it, everything changed. My pecs balanced out within four to eight weeks of just the normal lifting I was already doing — bench pressing, machine press — simply because I could finally load through a full range of motion without compensating.
Here's the three-step process I wish someone had shown me years ago.
Step 1: Test Your Shoulder Extension
We need to test your shoulder extension and look at how you're moving — specifically, whether you're compensating. And as a heads-up, not many people actually know how to spot compensations when they test mobility.
A lot of people suggest testing shoulder internal rotation for this, but that never really made sense to me. Who's actually pressing with their shoulders at 90 degrees, elbows flared out? Even after improving my shoulder IR, I still dealt with this issue. My pec still wasn't growing. It wasn't until I brought my arm closer to my body and tested shoulder extension and internal rotation under pressing mechanics that I saw real progress.
Here's how to do it: turn your thumb backward and reach behind you. While you do this, watch for these four compensations.
Excessive shoulder rounding. If your shoulder rolls so far forward that you can't see your sternum or chest muscles, you're probably limited. Stop the test there.
Leaning forward. You're hunching or going into kyphosis to make up for a lack of mobility in the shoulder itself.
Elbow bending. When you reach back and your elbow kicks out to the side and bends, that means the pecs are staying shortened — they're not actually lengthening.
Shoulder hiking. Your upper trap takes over and the shoulder moves up and over the actual extension your shoulder joint should be providing.
If you can't get to at least 45 degrees of shoulder extension — or if any of those compensations show up before you get there — you've got some work to do.
Step 2: Mobilize
Now that we know whether your shoulder is limited and how you might be compensating, let's work on opening up the pec musculature and improving how your shoulder internally rotates and extends.
Foam Roller Lat Smash
This is a great starting point for loosening up the shoulder musculature and gaining some initial shoulder extension and internal rotation mobility.
You'll need a foam roller and something heavy to hold — a dumbbell or kettlebell. Set up on your side with your knees at about 90 degrees and place the foam roller underneath the nipple line, or right below the armpit area. You don't want to be so high that your shoulder is shrugging up — just below it.
Once you're stacked in position, take the weight and reach it straight up to the ceiling. Keep your eyes on it if you can (but look forward if it strains your neck). This adds extra weight to your body so you can put more pressure through the serratus and lat area.
While the weight is reaching up, rotate your arm between external and internal rotation. Palm opening toward your ear is external rotation — breathe in through the nose. Palm facing down toward your hip is internal rotation — exhale as you go.
One tip: if you're not feeling enough pressure through the lat, make sure your side isn't drooping to the floor. You may need to hold a semi side-plank position to put all that weight and pressure through the lat. A lot of people sag down and their obliques touch the floor, and they wonder why they're not feeling it.
Do two rounds on each side, eight to ten reps total (including both rotation directions).
Quadruped Breathing
This solidifies the mobility you gained from the lat smash and starts building some coordination and control in an isometric position. It also improves your ability to breathe into the rib cage, creating expansion around the chest, shoulder, and shoulder blade — like a stretch from the inside out.
Set up on all fours. You can place a foam roller, yoga block, or ball between your knees for some inner-thigh activation. Knees directly under hips, elbows directly under shoulders, and go into a slight protraction at the shoulders.
Palms can face down (the goal) or up toward the ceiling. If you're getting a ton of upper trap tension and feeling your neck working overtime, flip your palms up. That usually solves it.
From there: exhale everything out, empty the tank, squeeze the foam roller slightly between your knees, hold your breath for three to five seconds, then take a slow, gentle inhale while maintaining any abdominal tension you gained. You're not crunching or flexing your abs — just getting expansion through the entire rib cage.
Watch for excessive upper-back rounding or shoulder shrugging. If you catch yourself doing either, take a deep breath, pull your shoulders up toward your ears and then actively pull them down toward your hips, then protract. That usually fixes it.
Two sets of three to five full breaths.
Dead Hang Variation
Everyone's done some version of a dead hang, but this setup is different. You put your feet out in front of you, creating a more stable, relaxed position. The typical dead hang lets people extend too much through the low back, and the spine steals some of the mobility that the shoulders should be gaining.
Grab a pull-up bar, Smith machine bar, or anything sturdy just outside shoulder width. Set your feet directly in front of you, creating roughly 90 degrees at the hips and knees. Drag yourself slightly forward so your hips are in front of your shoulders. This decompresses the spine, stretches the lats and pecs, and puts you in a much better position to actually get shoulder mobility.
From here, exhale fully, hold the abdominal tension, then inhale and breathe up into the rib cage. You should feel a huge expansion all around your shoulders. It's going to feel like you're peeling meat off the bone — and if you get that sensation, you're probably doing it right.
This one is intense. Two sets of three to five deep breaths.
Retest
After doing one to all three of these drills, retest your shoulder extension. You need to know if it's actually helping. The test and your mobility will guide you — not any specific drill or protocol. I don't care what the intervention is, just get the change and then load it.
Step 3: Load It
This is where it all comes together. We're not just chasing mobility for the sake of it — we're loading these new ranges of motion so your body learns to use them and your pec can finally do its job.
Alternating Floor Press
The floor limits how far your elbow can go behind your body, which helps reduce the risk of compensation. A plate-loaded machine chest press works well here too — just bring that elbow to the rib cage and don't go further back unless you genuinely have that range of motion.
Watch for your lower back arching. That's one of the most common ways people fake shoulder mobility during pressing.
Half-Kneeling Cable Press
This is a progression toward deeper ranges of motion. The half-kneeling position locks your hips and spine, forcing your pec and shoulder to do the work while you relearn clean pressing mechanics. It's a great accessory exercise later in your push day.
The loading potential here is lower than the floor press — you can go much heavier on the floor press. But this one is for maximizing the mobility component while still building strength and coordination.
Return to Bilateral Pressing
When you're ready to get back to barbell bench pressing, don't just jump into momentum-based, huge-arch pressing. Use variations like a Larsen press or pin bench press. You may even want to start with a reduced range of motion — not fully touching your chest — and build into it over time.
The most important element here is a pause at the bottom of the movement. Using safeties or pausing on your chest takes the stretch reflex out of the equation, forcing both pecs to initiate the press and get the weight moving. Removing the momentum also prevents those compensations from sneaking back in.
At this stage, you can start reintroducing some arching and scapular retraction, especially if you're working toward heavy bench press numbers again.
How to Program All Three
These three steps are dependent on your situation. You might want to add 20 pounds or so to your floor press before progressing to the cable press. In my personal experience, I used all three movements at the same time — floor press and bench press as my primary and secondary movements, and the cable press as an accessory later in the week within a full-body training plan.
What If You're Dealing With More Than Just Uneven Pecs?
If your posture is off, your mobility is limited, and your training always feels like one step forward and two steps back, this same three-step process — test, mobilize, load — applies to your entire body. That's the foundation of my Broken to Beastly protocol.
You can grab the full PDF program and ebook on my website, or if you just want the program itself at a fraction of the price, it's available inside the WaughFit app along with seven other programs, an exercise library, and constant updates.
Ready to Figure Out What's Actually Going On?
If you want help identifying your specific limitations and building a plan around them, I offer a free posture and mobility assessment where we can look at your movement, spot compensations, and figure out whether working together makes sense.
This post is based on my YouTube video "How to Permanently Fix an Uneven Chest." Watch the full walkthrough above or on my YouTube channel.