BOSTON (Reuters) - Slowly building strength with upper-body weight-lifting can relieve some of the arm and hand swelling that occurs in breast cancer survivors who have had lymph nodes under their arms removed, US researchers said on Wednesday.

After a year, women who did a twice weekly workout while wearing a compression garment had less arm pain and swelling, a condition known as lymphedema.

"Weight lifting reduced the number and severity of arm and hand symptoms, increased muscular strength and reduced the incidence of lymphedema," a team at the University of Pennsylvania School of Medicine reported in the New England Journal of Medicine.

The finding offers hope for many of the 2.4 million breast cancer survivors in the United States. Nearly a quarter of these women have lymphedema, and many have been told to refrain from lifting anything heavier than 10 or 15 pounds for fear of making the condition worse.

"I am totally pumped about this," study leader Kathryn Schmitz said in a telephone interview.

"The idea that we can do something that would enable them to get back to their lives is huge."

Weights were increased gradually and the woman wore the equivalent of support hose on their arm to prevent fluid from accumulating. The symptoms surface because the body needs lymph glands to drain fluid. The glands are often removed during breast cancer surgery to keep the cancer from spreading.

"Although no cost analysis was reported, the weight-lifting intervention clearly has the potential to result in cost savings, not only by reducing direct health care costs but also by potentially reducing the risk of disability and allowing women to return to work at full capacity," Wendy Demark-Wahnefried of Houston's M.D. Anderson Cancer Center said.