Why is one pec bigger than the other

A strict bodybuilding routine targeted towards developing the smaller pec will result in the development of this side & as a result will make your chest more even. Any unilateral chest exercise is very beneficial for evening out a chest assymetry as it will enable you to isolate and put more load on your weaker and smaller chest. Examples of this include:Unilateral dumbbell chest pressCross body seated chest press. One arm low dbell FlyUnilateral resistance band fly

Before you get started training to even out your uneven chest it is important to note that: I do not recommend only training the smaller side, so please still train both sides.

You should find that your bigger pec is stronger, so I recommend that you simply train your smaller pec first and then match the amount reps you did on your smaller pec with your bigger pec.

I've always had a problem with my right pec being slightly bigger than my left and I think its due to the fact that I am right handed and do most things with my right hand. A managed to fix it about a year ago by doing dumbbell bench press, but I stopped lifting for a year and lost about 30 lbs so I'm back to square one. Recently I have started to do the Stronglifts 5x5 workout and was wondering if I should incorporate a dumbbell press workout into the routine or if I should leave it for now and stay true to the original workout?

Today I’m going to show you how to fix your uneven chest. I have uneven chest muscles so I understand how much it sucks. The good news is I also know how to fix it and I will explain to you exactly how to do it.

In this article you will learn the causes of uneven chest muscles and the techniques/exercises you can do to fix it. Plus a few other tips to even out your chest that you won’t find anywhere else.

This is a 2,500 word article filled with information so get cozy, read it top to bottom, and let me know if you have questions.

My Uneven Chest Story

When I started lifting I wanted a strong chest like many young men do. I wanted chiseled pectorals that spanned proudly across my ribcage. “Gladiator Pecs” they used to call them back in the Golden Era of bodybuilding.

For years I did my push-ups, chest presses and dumbbell flyes faithfully in hopes that one day my chest would look like He-man’s. But to my dismay one pec grew larger and larger while the other barely grew at all.

My left pectoral muscle grew large and full. It felt strong when I lifted. I could feel it engage without even trying. But my right pec was puny. It looked wimpy. The muscle was flat and felt ‘loose’. What the hell?

It seemed like my right pectoral was missing a strip of muscle fibers along the top near my collarbone. There was less meat in the middle of my right pec compared to my left one.

My left pec was dense, full, and had a great shape to it. It got nice and pumped during training and I could feel it working every time I trained. It felt great and I wanted the other pec to feel the same but I just couldn’t get the same effect. My right chest muscle just stayed flat no matter what I did.

All I wanted a nice, full, balanced chest, but had two lop-sided pecs instead and it drove me crazy. I tried everything to fix it but nothing seemed to work. I was completely discouraged. It was so bad that I stopped training my chest all together because I didn’t want it to get any worse. I took a full 6 months off from chest training because I didn’t want to deal with the disappointment.

The Turning Point

I finally had enough and made up my mind to fix my uneven chest. I was pissed off because I spent so much time and energy in the gym pursuing a perfect body and I was going to have it – complete with a strong symmetrical chest.

After obsessing about my condition for months I began thinking of new ways to fix it. I slowly eased back into chest training, this time with a new outlook.

Over time I was able to fix my uneven chest. It’s not perfect, but it’s way better than it was before. In order to fix an uneven chest you need to know what caused it in the first place. That way you can correct the problem at the source.

What Causes Uneven Chest Development?

There are several reasons for an uneven chest. Some you can control and some you cannot. Luckily, most cases can be corrected if you put in the required time and effort.

Uneven Chest Structure

The shape of your rib cage obviously plays a part in how your chest looks. As well as how your chest muscles connect to your bones. If your ribs stick out farther on one side of your chest, or if your pectoral muscle insertion points are not symmetrical there’s not much you can do about those issues directly.

In rare cases there could be a missing section of muscle due to genetics or trauma. These issues are harder to fix but improvement is possible with the right adjustments.

That being said, an uneven chest is more likely self induced rather than genetic or structural. Whether your chest imbalance is structural or caused by something else, muscle and bone can be reshaped over time but this process is very slow. More on this topic later.

Weak Mind-Muscle Connection

Mind-muscle connection plays a big role in building muscle. It may even be the most important factor the determines muscle growth. You must be able to flex your muscles extremely hard, and hold that contraction, just by thinking about it. By using you ‘mind power’.

You need to consciously ‘plug in’ to the muscle you’re training. Without the neurons in your brain signaling your muscle fibers to contact, it’s hopeless. Luckily mind-muscle connection is a SKILL you can build with practice.

Synergistic Dominance

Weak mind-muscle connection with your chest muscles typically results in (or is the result of) an overactive shoulder and tricep muscle. Lets say you are performing bench press and you feel your shoulder and tricep muscle doing most of the work on the side with your weaker pec. This is called synergistic dominance, meaning the secondary muscles (shoulder and tricep) for the pressing motion take over the primary mover (pectoral). If not corrected synergistic dominance can be hard to reverse.

Along those same lines, sometimes the trapezius muscle on the side of the smaller chest muscle is overactive. When this happens the trap muscle gets stronger signals from the central nervous system than the chest muscle. This is called altered reciprocal inhibition and it causes muscle imbalances by minimizing the neural drive to the chest muscles.

Bad Lifting Form

Obviously, bad form leads to muscle imbalances. Sometimes it’s as simple as changing your movement slightly. Maybe changing the angle of your elbow or shoulder joint by a few degrees is all that is necessary. Or a tiny change in grip. Either way your thought pattern of how to perform the exercise makes a big difference. How you think about moving the weight changes the movement pattern. It’s very important to lift slowly and control your reps. The wrong form also undermines your progress by preventing the best results possible.

Maintain proper form throughout the entirety of each set. Every rep should be performed with laser precision. When form breaks down, the weight shifts from one side to another, or one muscle group to another. This requires a lot of practice, self analysis and experimentation. You need to find your ‘groove’ for each chest exercise so that you get the results you want.

For this reason people with an uneven chest typically have an over-developed shoulder on the side with the small pec to compensate (synergistic dominance). The tricep and traps could become over-developed here for the same reason.

If you’re dealing with an uneven chest, you need to be extra vigilant about form. It takes a lot of focus to fix but it’s the only way. If you let up on focus even slightly then you will fall back into the old habit and the problem will get worse.

How to Fix Your Uneven Chest Muscle

No matter the cause of the imbalance or how bad it is, it can always be improved. The #1 thing you must do in order to even out your chest is engage the lagging side properly. There are a few thing you need to do in order to even your chest muscle. (Note there are specific cues for each chest exercise. I’ve include cue for the chest press and dumbbell flyes later in this article. However, there are many more that are beyond the scope of this article.) We will cover general things you can do to improve your chest muscle balance. They are:

1. Build Stronger Mind-Muscle Connection
2. Improve your lifting form
3. Stretch
4. Breathe properly
5. Exercises technique

Build Stronger Mind-Muscle Connection

Mind-muscle connection is what makes a great physique. Mind-muscle connection is using ‘mind power’ to flex your muscles. Through concentration and focusing your mental energy into the lagging muscle you can make it grow.

Flex Your Pecs to Improve Mind-Muscle Connection

Here’s the drill: Contract your lagging pec muscle as hard as you can. Hold the maximum flex as long as you can. Do this everyday as often as you think to. Especially do this before training chest. Perform the “side-chest” bodybuilding pose to flex your weaker pec. Do this often and do it between sets while at the gym.

Flex the weaker side before each set. Hold the muscle contraction as hard as you can for as long as you can. Before I do my first exercises on chest day, I flex the lagging pec until I have a pump and my skin looks red from the rush of blood into the muscle. Once I feel like I’m ‘connected’ to my muscle I begin lifting.

Slower Reps to Focus on Muscle Connection

Take 3 seconds to lower the weight and 2 seconds to lift it. Take your time with each rep. Feel the chest muscles stretching and squeezing.

The lifting phase of each rep should start with the contracting the muscle to move the elbows through space.

Concentrate 100% on Your Chest

Don’t let your mind wonder while training. Concentration is a CRITICAL piece of the bodybuilding puzzle. Even a split second lapse in concentration could mean disaster.

Count your reps, count your tempo, and most importantly visualize in your mind’s eye your chest muscles working. Visualize your pectoral muscles stretching across your rib cage while you lower the weight and then contracting as you’re lifting.

Focus on contracting you muscle as hard as you can throughout the entire range of motion. This ensure your chest muscle won’t slack.

Stretch Your Chest Muscles

Stretch your chest muscles between sets. This stimulates growth and gives muscles a nice shape. More importantly stretching gives you a sensation in the muscle you can feel. This feeling helps you hone in on the muscle to help build mind-muscle connection.

Chest Stretches

• Doorway Stretch – Rest your elbow on the edge of the doorway. Lean forward through the doorway to stretch the chest.
• Weight Assisted Stretch – Grab two light dumbbells and lay on a bench like you’re about to do chest flys. Let the dumbbells stretch your chest. Breath deeply to expand your ribcage and enhance the stretch.

Corrective Stretching

Static Stretch: Hold a doorway stretch for a minimum 30 seconds. Do this for your larger (overactive pec). It will cause it to relax. Now, stretch your upper and middle trapezius muscle on the side of the weaker pec and hold it for 30 seconds. This makes your trapezes muscle relax and will prevent altered reciprocal inhibition by allowing proper neural drive to your pectoral muscle.

Improve Your Lifting Form for Chest Training

Small tweaks to your body positioning can make a huge difference in muscle engagement. Below are some tweaks I’ve found to be helpful. Remember to always lighten the load when trying something new.

Pull in Your Gut

An uneven chest can be the result of weak core muscles of an imbalance in another part of the body. This helps create core stability and helps puff out your chest. Suck in your gut to expand your chest more. Imagine pulling your belly button back to your spine.

Flex Your Glutes

Flex your glutes together HARD when lifting. This will create stability and engage your core so there’s no slack in your body anywhere. No slack means no shifting around so the tension stays on your chest muscles evenly while lifting.

Tuck Your Chin

Keep your head straight focus your gaze on a spot and hold it there the entire set. When training chest, tuck your chin and rest the back of your head on the bench. REST, don’t press your head into the bench.

Pressing your head into the bench causes your trapezes muscles to engage more, which is something you might want to avoid if you suspect your traps are overactive.

Keep Your Chest High

Imagine trying to touch your chest to the ceiling. This prevents the chest muscles from slacking and helps keep tension on them.

Breathe Deep

Fill your lungs with as much air as possible each time you inhale. Deep breaths naturally put you in a good body position.

These take practice. It’s important to listen to your body’s feedback so you can make adjustments if needed. You should literally feel like you’re GULPING AIR to fill up your lungs as much as possible each rep.

Improper breathing causes weird tension throughout your body and collapses posture. This compromises your form. Poor breathing also leads to muscle imbalances.

How to Fix Your Uneven Chest Video

This video is an overview of how tight muscles in your back and shoulder can cause and uneven chest, and what you can do about it.

Trigger Point Release for Better Chest Muscle Activation

This video shows you how to do self-message technique called trigger-point therapy (sometimes called myofascial release). An uneven chest is typically a symptom of tight back muscles.

Try this technique before your chest workout to improve you chest muscle activation by getting your tight back muscles to relax.

Exercises for Fixing an Uneven Chest

Here are a few exercises you can do in addition to your normal chest training routine to help engage your lagging pec.

Floor Presses

Shorten the range of motion and provides stability so you can focus on your chest muscle working.

One-Arm Presses

One-arm presses from the floor or bench. I do one-arm presses at the end of my chest workout and target my weaker side. I perform these holding just one dumbbell. No weight in the other hand to counter-balance. I sometimes lift my feet off the floor too.

This forces me to engage my torso and core muscles for stability. This strengthens any weak points in my foundation that might exist. This also forces me to go very slow and under control so I maintain balance.

One-Arm Flys

These are similar to one-arm presses. Although sometimes I will keep my feet on the floor for balance.

Pullovers

Pullovers performed with a dumbbell or barbell are one way to ignite the chest.

(Slight) Incline Bench

I find that a slight incline (under 30 degrees) helps engage my chest. The angle helps use the weight to pack your shoulders against the bench and maintain good form.

(Related: I recently posted an article with the 3 best exercise to fix your uneven chest. They are more advanced but very effective at fixing uneven chest muscles.)

Exercise Adjustments for Uneven Chest

Affiliate Disclosure: I may receive a small commission when you click a link and buy a product/service.

Try these exercise adjustments for better pec engagement.

Dumbell Flyes

Twist your wrists to bring your pinkies together as you approach the top of the movement. You don’t need to touch the dumbbells together, just twist your wrist so your palms face your head.

Dumbbell Chest Press

Touch all 4 bells together at the top of the movement. Slowly bring them together and slowly press them into each other. Obviously in both of these exercises, it only works if you maintain the proper form mentioned earlier in this post. Get a pair of dumbbells and you can do these every day from home.

Supplements for an Uneven Chest

Obviously, there is no supplement that will directly fix an uneven chest. But one thing you want to make sure of is to be getting enough protein and eating in a slight calorie surplus. This way you have all the material needed to build up your smaller chest muscle.

A quality protein powder can help you reach your minimum protein and calorie requirements.

In Conclusion

The number one way to fix an uneven chest is to concentrate.

You will need to tweak body awareness. body articulation will be key. understanding your bodies feedback is important.

Try, experiment, and THINK. Analyze and make adjustments. Video record yourself lifting so you can analyze form.

Leave a comment below if you need help.

The ‘Fix Your Uneven Chest’ Program Available soon!

The response to this article has been overwhelming. People have reached out from all over the world for help. It’s hard to help everyone because I am just one person, so I did the next best thing and am writing a book about how to fix an uneven chest.

The book will contain everything you need to help fix your uneven chest. It will have all the exercises, training techniques and methods I used to even out my pecs. This book is for you if you want a step-by-step guide for building a balanced chest. It’s full of stretches and exercises to fix you uneven chest no matter what the cause.

This book will be the definitive guide to fix an uneven pecs and build a strong balanced chest. Sign up for the email list to be the first to know when it drops.