What People With Breast Cancer and Survivors Should Know About Exercising After a Mastectomy

October 4, 2022
Sean Smith, MD

Sean Smith, MD, is the medical director of the University of Michigan Rogel Cancer Center’s Cancer Rehabilitation program. Dr. Smith has a clinical emphasis on restoring function and reducing symptom burden in people with a history of cancer. He serves on the editorial board of the Archives of Rehabilitation Research and Clinical Translation. He led the American Society of Clinical Oncology (ASCO) Education Committee for Symptoms and Survivorship and currently co-chairs the American Academy of Physical Medicine and Rehabilitation’s Cancer Rehabilitation BOLD initiative. His research emphasis is the assessment of function in people with cancer. You can follow Dr. Smith on Twitter.

A mastectomy is an important type of surgery that oncology teams use to treat and sometimes prevent breast cancer. During a mastectomy, a surgeon removes the entire breast. Unfortunately, after the procedure, it may be more difficult to use your shoulder, and sometimes pain can develop. When combined with other cancer interventions, such as radiation therapy or an axillary lymph node dissection (in which the surgeon removes several lymph nodes under the arm), the risk of developing problems after a mastectomy increases.

Fortunately, there are exercises and self-management tools people can use after a mastectomy to reduce pain and improve use of the shoulder.

How a mastectomy can impact your muscles

The most important thing to remember after a mastectomy is that the muscles in the front of the chest, including those around the shoulder, often get tighter. This can be for several different reasons, including that the muscle itself has shortened, scar tissue has developed, or the muscles have been impacted by breast reconstruction.

The largest and strongest muscle around the shoulder is called the “pectoralis major,” often called the “pec” for short. This muscle performs 2 primary actions: it pulls our arm forward and inward. You can feel your pec by bending your elbow and bringing it to your chest.

While it’s good to have strong muscles, if the pec becomes too tight, it can cause long-term problems. For example, it can become tough to reach overhead or behind. It can also cause other muscles to be stretched too tight or even get pinched. A tight pec muscle can lead to other shoulder problems, too, like rotator cuff tears, muscle pain, and even neck pain.

A good exercise program is critical to preventing problems from a mastectomy, including those that affect nearby muscles. Exercise can often relieve existing pain and tightness after a mastectomy, too.

What to consider before exercising after a mastectomy

Before starting exercise after a mastectomy, you must first make sure that your surgeon has cleared you to do so. Often, there may be some limitations in lifting and stretching until you are healed. However, some motion is typically encouraged after the procedure, and you should absolutely perform exercises within the limitations your surgeon has set. Talk with your doctor about how long you have to wait after the procedure to exercise and what kind of exercise they recommend.

If you had breast reconstruction with an implant or a graft, your limitations may last longer than if you had a mastectomy without these procedures. If you are considering breast reconstruction, talk with your surgeon about how it may affect your shoulder, as new research is emerging about different reconstruction approaches and long-term shoulder function.

Getting started with exercise after a mastectomy

A good exercise program after a mastectomy starts with stretching your pec muscle. This can be done in a doorway, on a foam roller or similar soft and elevated surface, or with the help of a physical therapist or exercise trainer familiar with the surgery. To stretch the pec muscle, place your forearm against a door frame and step one foot forward, slowly leaning into the stretch. You should feel it across your chest.

In addition to stretching the pec muscle, strengthening the surrounding muscles is essential. This means making the upper back as strong as possible and giving your body a solid set of core muscles to support the shoulder and neck. Exercises like Pilates are great for this because they do not put a lot of strain through your back or neck. Yoga and other exercises may help, too. These exercises may also reduce the risk of other potential complications after a mastectomy, like lymphedema.

How cancer rehabilitation can help after a mastectomy

If you have been dealing with long-term pain or tightness following mastectomy and can’t seem to improve it with stretches and exercises on your own, seeing a cancer rehabilitation specialist may be useful. There are physicians who are board certified in Physical Medicine & Rehabilitation (PM&R) and specialize in treating the effects of cancer and improving function. Additionally, physical therapists may receive certification to treat the effects of a mastectomy and can be incredibly helpful in guiding a person through their exercise program and reducing pain. Finally, occupational therapists are experts in preventing injury and adapting your life around a “new normal” to maximize what you can do. There are also physical and occupational therapists who specialize in lymphedema therapy, if that is needed. Talk with your health care team to see if a referral to a cancer rehabilitation specialist may be helpful.

Not all pain and tightness after a mastectomy are from a muscle shortening. Pain and tightness may also be caused by nerve endings that are tender to the touch, muscles that are in spasm (like a Charley horse), or areas of inflammation that are causing pain. A PM&R doctor should be able to evaluate and treat these issues, including with procedures or medications if the situation calls for it.

It is important that anyone who has received a mastectomy understands that rehabilitation is an important way to prevent pain and improve use of their shoulder and arm. If you feel stuck, reach out to your surgeon or health care team and ask for a referral to a cancer rehabilitation specialist. Your problems may not be obvious, and it is important to advocate for your overall wellbeing, even after the surgery is over.

The author has no relevant relationships to disclose.

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