April 15 -- Exercise can help improve breast cancer patients' quality of life while they undergo treatment, a new study indicates, according to a HealthDay News.

University of Miami researchers examined the physical activity levels and mental/physical health of 240 women with non-metastatic breast cancer (it hadn't spread to other parts of the body) who were recruited for the study four to 10 weeks after surgery.

The women who were physically active had less depression, less debilitating fatigue and a better quality of life during cancer treatment after surgery.

"Women who are physically active may also have more confidence in their own ability to continue with family-related, household, work-related or social activities, which bring meaning and satisfaction to their lives. This may lead to appraisals of lower fatigue, heightened quality of life and less depression," study author Jamie Stagl, a doctoral student in clinical health psychology, said in a university news release.

The same researchers previously found that stress management improves breast cancer treatment.

The study was slated for presentation Friday at the Society of Behavioral Medicine's annual meeting, in New Orleans.

Data and conclusions presented at medical meetings should be considered preliminary until published in a peer-reviewed medical journal.