After reviewing published evidence, University of Missouri researchers conclude the benefits of exercise outweigh the risks for breast cancer survivors, including those who develop lymphedema, a chronic swelling that commonly occurs after breast cancer treatment. Co-author Jane Armer, professor in the University’s Sinclair School of Nursing, and colleagues, write about their findings in the December 2011 issue of the Journal of Cancer Survivorship.
Armer told the media, “exercise can be beneficial and not harmful for breast cancer survivors,” and patients at risk for lymphedema, a condition that affects around 3 million people in the US, can exercise if they are careful and watch what they are doing:
“Each individual should balance the pros and cons of the activity she chooses, but keep in mind that being sedentary has risks and being active is beneficial in many ways, including possibly reducing the risk of cancer recurrence,” she added.
Lymphedema usually results when lymph nodes are removed or treated with radiation as part of cancer treatment. It can develop any time after treatment, and traditional thinking was that patients should avoid exercise in case it prompted development of the condition.
But Amer and colleagues found patients who exercise were at no greater risk of developing lymphedema than those who do not exercise. Furthermore, exercising once lymphedema has developed does not make it worse.
“Breast cancer survivors do not need to restrict their activity as we once thought,” said Amer.
“If patients want to be active, they should carefully condition their bodies by increasing repetitions of resistance exercises under proper supervision,” she added.
However, Amer said more studies would be needed to establish whether exercise actually prevents lymphedema.
For their review, Amer and colleagues searched the available literature and found 19 studies out of over 1,000 potential articles met their stringent inclusion criteria.
Seven of the studies covered resistance exercise, another seven covered aerobic and resistance exercise, and five studies covered other forms of exercise.
“Studies concluded that slowly progressive exercise of varying modalities is not associated with the development or exacerbation of breast cancer-related lymphedema and can be safely pursued with proper supervision. Combined aerobic and resistance exercise appear safe, but confirmation requires larger and more rigorous studies,” write the authors.