Does Submuscular Breast Implant Placement Affect Pectoralis Muscle Function?

If you’re considering breast augmentation with implants placed under the muscle, you might wonder how this affects your chest strength. It’s a great—and important—question I get from patients, especially those who are active or athletic.

I’m Dr. Victoria Aimé, a plastic surgeon in Scottsdale, AZ, and in this post, I’ll explain what happens to the pectoralis major muscle during submuscular implant placement and what it means for your function long-term.

What Is the Pectoralis Major and What Does It Do?

The pectoralis major is the large, fan-shaped chest muscle that extends from your clavicle and sternum (the breastbone) out toward your shoulder. Its primary roles include:

• Adduction: Pulling your arm toward your body
• Internal rotation: Turning your shoulder inward
• Assisting with movements like pushups, chest presses, and hugging motions

What Happens to the Muscle During Surgery?

In submuscular (or subpectoral) breast augmentation, a portion of the lower pectoralis muscle is released—typically along the lower border and sometimes partially at the sternal edge. This allows the implant to be placed beneath the muscle while still maintaining upper muscle coverage.

How Does This Affect Muscle Function?

Studies in plastic surgery literature show that after this procedure:

• Most patients experience a temporary decrease in pectoralis muscle function, typically in the range of 3% to 20%
• The functions most affected are adduction and internal shoulder rotation
• Over time, patients often compensate with surrounding muscles in the shoulder girdle, such as the deltoids and latissimus dorsi

For the average person, this mild loss of function does not impact daily activities like carrying groceries, typing, lifting children, or working out recreationally.

Who Might Notice a Difference?

The people most likely to perceive changes in chest strength after submuscular augmentation are:

• Competitive athletes
• Bodybuilders and powerlifters
• Rock climbers
• People regularly performing high-resistance chest exercises

If you fall into one of these groups, we’ll discuss your goals in detail and may explore other pocket options (like subfascial or subglandular placement) that minimize muscle disruption.

Is Atrophy a Concern?

Yes—some degree of pectoralis muscle atrophy (thinning) is expected over time when an implant is placed beneath it. This doesn’t mean the muscle becomes non-functional, but it may appear flatter on imaging or physical exam. Again, this typically isn’t noticeable in most women unless you’re very lean or doing high-level strength training.

Bottom Line

Submuscular breast augmentation can cause a mild and usually temporary reduction in chest muscle function, especially for movements like adduction and internal rotation. But most patients compensate naturally over time and don’t experience limitations in daily life.

If you’re an athlete or rely heavily on upper-body strength, we’ll tailor your surgical plan accordingly and talk through the pros and cons of each pocket option.

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Ready to explore breast augmentation options?

My goal is to help you make informed, confident decisions about your body with an approach that balances aesthetics, function, and long-term health.

-Dr. Victoria Aimé

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