Pectus Excavatum and Uneven Chest Muscles in 2022 – 8 Tips + 4 Mistakes & More

Evidence Based This post has medical citations

It is widespread for people with pectus excavatum to have uneven chest muscles. Fortunately, you can repair this non-surgically. I used to be a victim of this, but I improved it with specific functional training.

Before I started weightlifting, the asymmetry was much more noticeable. My right pectoral muscle used to be a lot smaller than my left one. 

Importance of Unilateral Exercises

The best way to correct this is to perform unilateral exercises in the gym. That way, you will focus on one chest muscle at a time. 

When you perform the one-arm dumbbell fly, you will isolate one chest muscle. Use mind-muscle connection, and focus on squeezing the muscle with each rep. 

4 Common Mistakes

1. Stop Training the Weak Side Only

A big mistake a lot of people suffering from an asymmetrical pectus excavatum is that they train the weak side only. Don’t do this because you can end up with worse imbalances. Remember that training both sides equally is crucial for a symmetrical and aesthetic chest appearance. 

Remember that you can’t wholly improve muscular asymmetry because of genetics. No matter how much you train for perfect symmetry, you won’t fix it completely. In most cases, the muscle is just inserted at a different place.

Nobody is perfectly symmetrical, whether you look at their facial shape or body. You can’t change the structure of your physique and the placement of the muscles. But, you can change the size of the muscle, which is everything you need. 

2. Posture Neglecting Throughout the Day

Chest muscle imbalances can happen from what we do in our everyday life. I am very guilty of slouching in my computer desk chair, leaning to my right side. It only takes a few days until your body adapts to this improper sitting position.

This leads to one shoulder, usually the left, remaining higher than the other. When you take that exact improper posture to the weight room without correcting it, problems occur. 

3. Barbell Bench Pressing Problem

For example, one pectoral muscle will do more work if you do a flat barbell bench press with this posture. You will unevenly position the elbows because the left shoulder is higher, producing unequal force.

If you’re a fan of barbell bench press, the first thing you want to do is swap this exercise using dumbbells. When you use dumbbells, it forces you to command each side individually.

Try to move the dumbbells simultaneously when you do the training, so you don’t have to rely on one side stronger than the other. 

Another Problem

The number one reason for this problem is failing to keep the shoulder fixed in place when performing the bench press. Suppose you struggle with the pectus excavatum asymmetrical chest. In that case, you will probably feel more pump on one side of your chest and shoulder.

If you can’t feel this, the most significant thing you can film yourself. Get somebody to film you so you can better identify the problem. 

Sometimes the cause of why your shoulder is rounded and not fixed in place is because you have weak back muscles. That causes an inability to keep the shoulders retracted and set in position. Please consider strengthening those muscles. 

Stay Away from Barbell Bench Pressing

If you suffer from pectus excavatum uneven chest muscles, I would recommend you stay away from barbell bench pressing for a while until your issue gets fixed. That’s because one side will always do more work than the other.

Shifting to dumbbells will be the best choice for you, as they are separate from each other, and you will focus on the weaker side more. 

4. Lack of Symmetry Throughout barbell Exercises

Another cause is a complete lack of symmetry. One arm is doing something completely different than the other. Sometimes you may bring one dumbbell wider and the other closer to your chest muscles while doing the dumbbell bench press.

The wider side activates the chest muscle more, while the other side involves the triceps. 

The solution to this is to film yourself or be more aware of your body in space. Yoga can be very beneficial for this. 

8 Steps to Correct Asymmetry

1. Repair Issues One by One

As someone who wants to help people improve their pectus excavatum deformity and flared ribs non-surgically, I must analyze a sufferer’s overall body structure. I must pick up little things that aren’t noticeable to the average person but worsen the sunken chest wall appearance.

When you focus on fixing those minor physique issues one by one, you will notice how your pectus excavatum deformity becomes less noticeable. An example of this is chest unevenness caused by the pectus excavatum deformity. 

2. Evaluate Yourself in the Mirror

If you want to fix chest muscle imbalance, you must also know your physique and bodily movement. It all starts with looking at yourself in the mirror.

It can become one of the most effective tools to improve pectus excavatum and muscular irregularities. I sincerely believe that postural deformity causes most muscular imbalances. 

The problem that causes imbalance can be very subtle. Try to become very observant of your body to identify these minor problems. To do this, you need to pay more attention to your body movements while training. 

3. Start on the Weak Side

Always start on the side where your pectoral muscle is weaker and smaller. Then, do the same amount of repetitions on the stronger side.

That way, you won’t overload the stronger pectoral muscle, causing a muscular imbalance. The balancing of the muscles will not happen overnight. Allow the change to occur in a few months. 

The weaker pec will develop more than the stronger one when you start. The weaker one will grow because of higher training intensity and more energy when performing it first.

4. Unilateral Dumbbell Press Exercise

You press one arm at a time.

A solid mind-muscle connection is essential when you try to fix an uneven chest caused by pectus excavatum. 

Focus on this exercise a lot if you do a lot of bench pressing with a straight bar. You will activate your “sleepy” muscles with this exercise.

Dumbbell Unilateral Pressing Drop Set

Once you have finished the set using both dumbbells, put down the dumbbell of the stronger side to the floor. Do as many repetitions as possible with one dumbbell on the weak side. This will allow you to squeeze more and gain more mind-muscle connection over the weaker muscle.

If one is a lot smaller than the other, you’re probably lacking the ability to contract the muscle fully. Because the pecs are autonomous, you can have one side that is more neurologically turned on than the other.

That happens especially when you’re right-handed versus left-handed. To improve mind-muscle connection, use your free hand as a guide and touch your chest muscle throughout the exercise. Make your chest contract hard on your fingers. 

5. Add Volume to the Weaker Side

The second helpful thing you can do is add more volume to the weaker side. When you do a push workout, add a one-armed chest exercise to increase your overall volume.

For example, if you’re working out over a week, you want to add additional volume per cycle by adding just a few sets on the weaker side. You will see the pectus excavatum chest unevenness balance out with extra volume and mind-muscle control. 

6. Corrective Exercise

The easiest way is to grab light dumbbells, lean forward with your chest on an incline bench, and bring the shoulders back while squeezing the shoulder blades together.

Do this exercise with both simultaneously, and allow the weaker side to catch up. If you want to face the problem head-on, do this exercise on the weaker side only while supporting yourself on the bench with the other arm. 

7. Postural Problem

Many people will use a technique where they lift a little more weight on the weaker side or do a few extra repetitions.

This technique can work, but consider that uneven pectus excavatum is mainly caused by postural imbalance. Try to fix the problem at the root cause. The way to do this is to identify the problem in the mirror. 

Fix the Pectus Posture

Also, a lot of concave chest sufferers have rounded shoulders posture. What does this do to our chest muscles training?

What happens if we’re dominant with our right side, and our shoulder is rounded and internally rotated versus our left side? 

8. Focus on Body Movement

We all don’t have the luxury of working out with a personal trainer to watch you while you’re training and identify the muscular imbalances, particularly the uneven chest.

When you train by yourself, try to spot these postural imbalances so you can get rid of them while you’re training.

You can do it yourself; you need to pay more attention to your body alignment. I’d recommend you also lower the weights a bit so that you can develop the mind-muscle connection better. That’s how you will overcome this. 

The Bottom Line

Focusing on posture improvement and swapping standard barbell bench pressing with unilateral dumbbell press is a proven recipe to correct uneven chest muscles caused by pectus excavatum.

You can further worsen this problem by doing exercises improperly. The asymmetry doesn’t require surgical intervention to fix it. All you need is a mirror, a pair of dumbbells, and a solid mind-muscle connection.

If you have any questions about this issue, please comment below. Thank you for reading!

Article by:

Mihail Veleski

My name is Mihail Veleski. I used to suffer from the pectus excavatum deformity during my teenage years.

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