FRIDAY, June 1 (HealthDay News) -- Breast cancer survivors who participate in competitive sports can reduce their risk of relapse and improve their heart function, a new study suggests.

Researchers from the Sports Medicine Center in Florence, Italy, found regular high-level exercise is also linked to longer survival.

Dragon boat racing has gained popularity among breast cancer survivors because the sport involves a significant upper body workout. Researchers in Italy examined 30 dragon boat racers who completed treatment for breast cancer one year earlier and followed them over the course of four years. The heart function of each woman was evaluated at the beginning and end of each year, and compared to healthy female dragon boat racers.

The study revealed that the heart function of all the cancer survivors was within normal range, and their resting heart rate was even lower after four years of training.

"Cancer diagnosis and treatment can undoubtedly take a toll on the body and its physical stamina," lead researcher Dr. Laura Stefani said in a news release from the American College of Sports Medicine. "This study suggests that competitive sports activity has a positive impact on myocardial performance in women with breast cancer. Equally important, long-term competitive sport activity appears to have no negative impact on their cardiovascular performance."

The study was presented May 30 at the American College of Sports Medicine's annual meeting in San Francisco. Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

While the study uncovered an association between exercise and heart function in breast cancer survivors, it did not prove a cause-and-effect relationship.

More information

The U.S. National Cancer Institute provides more information on breast cancer and physical activity.