Breast cancer survivors who underwent a programme of progressive weight lifting demonstrated no increased risk of lymphedema in comparison to women who did not undertake additional exercise, concluded a US study presented at the San Antonio Breast Cancer Conference. The results of the study, published simultaneously online in JAMA, suggest that the health benefits of weight lifting should become available to all breast cancer survivors.

Lymphedema is a frequent complication among breast cancer survivors that can impair both a woman's arm function and quality of life. Clinical guidelines advise breast cancer survivors without lymphedema to avoid lifting children, heavy bags or other objects with their at-risk arm. This has led to concerns that adherence to such precautions may limit women's physical recovery after breast cancer.

Kathryn Schmitz and colleagues, from the University Of Pennsylvania School Of Medicine, undertook the Physical Activity and Lymphedema (PAL) trial to determine whether exercise was safe for breast cancer survivors at risk of lymphedema. Between October 2005 and February 2007, 154 breast cancer survivors, who had had at least two lymph nodes removed and no prior lymphedema diagnosis, were randomised to one of two groups -the weight lifting intervention group (who had a gym membership and 13 weeks of supervised instruction followed by nine months unsupervised gym access, n=77), or to a one year non intervention group (who were asked not to change their baseline line levels of exercise during study participation, n=77). The primary outcome was lymphedema onset defined as a 5% or more increase in arm swelling

Results show that the proportion of women who experienced breast cancer related lymphedema (BCRL) onset was 11% (8 of 72) in the weight lifting intervention groups versus 17% (13 out of 75) in the control group (P for equivalence =.04). Furthermore, among the subgroup who had five or more lymph nodes removed, the proportion experiencing BCRL was 7% (3 out of 45)in the weight lifting group versus 22% (11 of 49) in the control group (P for equivalence =.003).

"In conclusion, the findings of our study remove concerns that slowly progressive weight lifting will increase risk of lymphedema onset in breast cancer survivors," write the authors, adding that since the primary goal of the study was to test safety of weight lifting, not superiority, additional research will be needed before concluding that weight lifting prevents lymphedema.

In August 2009, Schmitz and colleagues published separate findings from the PAL trial showing that among women with lymphedema, those who took part in the slowly progressive weightlifting regimen experienced fewer flare-ups of their condition and a reduction in symptoms compared to women who did not lift weights.

Reference

K Schmitz, RL Ahmed, AB Trowel Weight lifting for women at risk for breast cancer-related lymphedema JAMA Doi: 10.1001/jama2010.1837