Exercise improves memory in breast cancer survivors

Moderate-to-vigorous physical activity is related to improved subjective memory in breast cancer survivors, who often complain about memory problems, reports a new Northwestern Medicine study. It appears the physical activity alleviates stress and benefits women psychologically, which in turn aids their memory.

A surprising finding is memory problems appear to be related to the high stress load cancer survivors experience, and may not be specific to chemotherapy or radiation treatments.

"Our research suggests these self-reported memory problems may be emotionally related," said lead author Siobhan Phillips, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. "These women are frightened, stressed, fatigued, tapped out emotionally and have low self-confidence, which can be very mentally taxing and can lead to perceived memory problems."

The study will be published July 8 in the journal Psycho-Oncology.

Phillips also is a member of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.

In the study, more physical activity was associated with higher levels of self-confidence, lower distress and less fatigue, which in turn is associated with lower levels of perceived memory impairment.

"We found moderate to vigorous physical activity actually benefits women psychologically and that, in turn, helps their memory," Phillips said.

Breast cancer survivors who had higher levels of moderate and vigorous physical activity --- brisk walking, biking, jogging or an exercise class -- had fewer subjective memory problems. Subjective memory is an individual's perception of her memory.

Investigators looked at memory and exercise in breast cancer survivors in two study arms: one in self-reported data for 1,477 women across the country; the other in accelerometers worn by 362 women. The findings linking improved memory to higher levels of physical activity were consistent across both groups.