Breast cancer survivors who take part in a supervised weight training program do not have a higher risk of arm swelling and discomfort (lymphedema), researchers from the University of Pennsylvania reported in JAMA (Journal of the American Medical Association). Cancer treatment, such as surgery to remove the lymph nodes, and radiation therapy can increase the risk of developing lymphedema.

The authors explain that: "Breast cancer survivors at risk for lymphedema alter activity, limit activity, or both from fear and uncertainty about their personal risk level, and upon guidance advising them to avoid lifting children, heavy bags, or other objects with the at-risk arm. Such guidance is often interpreted in a manner that deconditions the arm, increasing the potential for injury, overuse, and, ironically, lymphedema onset." Complying with these precautions may undermine physical recovery for breast cancer survivors.

Kathryn H. Schmitz, Ph.D., M.P.H., and team wanted to find out whether a 1-year weight-lifting program among breast cancer survivors might have an impact on the risk of developing lymphedema.

They carried out a randomized, controlled trial involving 154 females who had all been diagnosed with breast cancer from 1 to 5 years before entering the trial. They were all breast cancer survivors and had had 2 or more lymph nodes surgically removed, but had no detectable signs of lymphedema at the beginning of the study.

The women, aged 36 to 75, were randomly selected to: A Weight Lifting Group - they received weight lifting intervention, including membership of a gym and 13 weeks supervised instruction, followed by 9 months without an instructor, or.. A Control Group - they did no weight lifting exercise, had no gym membership or supervised instruction. 134 of the women completed the trial and were followed-up at the end of 12 months in August 2008.

The researchers found that: 11% (8/72) of the Weight Lifting Group women developed lymphedema 17% (13/75) of the Control Group women developed lymphedema The authors wrote: "Among women with 5 or more lymph nodes removed, the proportion who experienced incident BCRL onset was 7% (3 of 45) in the weight lifting intervention group and 22% (11 of 49) in the control group. Clinician-defined BCRL onset occurred in 1 woman in the weight lifting intervention group and 3 women in the control group (1.5% vs. 4.4%).

The majority of breast cancer survivors do not have lymphedema; however, they alter the use of their arms and upper body activities out of fear of developing lymphedema. The findings from our trial should help clarify clinical advice to patients who have completed breast cancer treatment regarding the safety of resuming or beginning a weight lifting program." The investigators stress that they focused on the safety of weight lifting for breast cancer survivors regarding lymphedema risk, and not whether this type of exercise is superior to other kinds of interventions. They add that further research is needed to determine whether weight lifting has a role to play in preventing lymphedema.

They wrote: "However, even with the finding of no harm, our results combined with previously published results for women with breast cancer-related lymphedema suggest that the many health benefits of weight lifting should now become available to all breast cancer survivors." "Weight Lifting for Women at Risk for Breast Cancer-Related Lymphedema - A Randomized Trial
Kathryn H. Schmitz, PhD, MPH; Rehana L. Ahmed, MD, PhD; Andrea B. Troxel, ScD; Andrea Cheville, MD, MSCE; Lorita Lewis-Grant, MPH, MSW; Rebecca Smith, MD, MS; Cathy J. Bryan, MEd; Catherine T. Williams-Smith, BS; Jesse Chittams, MS
JAMA. Published online December 8, 2010. doi: 10.1001/jama.2010.1837