MONDAY, Jan. 22, 2018 (HealthDay News) -- Longer survival after breast cancer may be as simple as staying fit, new research shows.
In the new study, regular exercise appeared to reduce breast cancer survivors' risk of heart disease, diabetes and possibly even the odds for breast cancer's return.
One breast cancer specialist said the findings should give survivors hope.
"A common question asked by patients who have recently completed treatment is 'What can I do to prevent this from happening again?' " said Dr. Alice Police. She is regional director of breast surgery at Northwell Health Cancer Institute in Sleepy Hollow, N.Y.
"We now have one more very well done study that supports the idea that exercise -- as opposed to weight loss alone -- is very important in preventing breast cancer recurrences," Police said.
The new research was led by Christina Dieli-Conwright, assistant professor of research, in biokinesiology and physical therapy at the University of Southern California (USC).
Her team tracked outcomes for 100 breast cancer survivors who'd received cancer treatment less than six months before entering the study.
Nearly half of the participants were obese and 77 percent had developed metabolic syndrome. That's a group of health conditions -- high blood pressure, excessive body fat and high blood fat levels -- that raises a person's odds for heart disease.
"Many people don't know the No. 1 cause of death for breast cancer survivors is heart disease, not cancer," Dieli-Conwright noted in a USC news release.
"In breast cancer patients, metabolic syndrome is exacerbated by obesity, a sedentary lifestyle and receipt of chemotherapy," Dieli-Conwright explained.
In fact, she added, women with metabolic syndrome are 17 percent more likely to develop a breast cancer, three times more likely to have breast cancer recurrence, and twice as likely to die from breast cancer, compared to women without the syndrome.
In the new study, women were randomly assigned to either a non-exercise ("control") group or to a group that undertook three one-on-one exercise sessions each week for four months.
The workout program included resistance training with weights as well as moderate-intensity aerobic exercise.
At the end of the four months, rates of metabolic syndrome were 80 percent in the non-exercising group, but they'd dropped to just 15 percent in the exercise group, the findings showed.
In addition, the women in the exercise group lost fat, gained muscle and reduced their risk of heart disease, the investigators reported. Also, among those in the exercise group, blood pressure levels fell by 10 percent and blood levels of "good" HDL cholesterol rose by 50 percent.
The bottom line, according to Dieli-Conwright: "Exercise is a form of medicine."
Police agreed. And while the study couldn't prove that regular workouts might thwart cancer's return, she said the theory makes sense.
"Exercise promotes changes in our bodies that go beyond how we look, and make all of our cells and organs happier so that we can remain cancer free," Police said.
Breast cancer specialist Dr. Stephanie Bernik is chief of surgical oncology at Lenox Hill Hospital in New York City. She said the study is important because "many cancer patients -- especially those undergoing chemotherapy -- become sedentary, and these habits often persist once treatment is completed."
But getting back into a workout routine is key to long-term survival, Bernik said, and "women that eat right and exercise are more likely to have a normal longevity."
The study was published Jan. 22 in the Journal of Clinical Oncology.
There are exercise tips for breast cancer survivors at Breastcancer.org.