Clinical research suggests that aerobic exercise helps prevent brain fog caused by chemotherapy

Many women who receive chemotherapy experience a decreased ability to remember, concentrate and/or think – sometimes called “chemo brain” or “brain fog” – both in the short and long term.

In a clinical trial of women starting chemotherapy for breast cancer, those who simultaneously started an aerobic exercise program self-reported greater improvements in cognitive function and quality of life compared to those who received standard care.

The findings are published online in the journal Cancer.

The study, the Aerobic Exercise and CogniTIVe Functioning in Women with brAsT cancEr (ACTIVATE) study, included 57 Canadian women in Ottawa and Vancouver who had been diagnosed with stage I-III breast cancer and were beginning chemotherapy. All women participated in 12-24 weeks of aerobic exercise: 28 started this exercise when they started chemotherapy and 29 started after completing chemotherapy.

Cognitive function assessments were performed before initiation of chemotherapy and after completion of chemotherapy (i.e., before the latter group began the exercise program).

Women who participated in the aerobic exercise program during chemotherapy self-reported better cognitive functioning and felt their mental abilities improved compared to those who received standard care without exercise. However, neuropsychological testing – a performance-based method used to measure a range of mental functions – revealed similar cognitive performance in the two groups after completing chemotherapy.

“Our findings strengthen the case for making exercise assessment, recommendation and referral a routine part of cancer care; this could help women living with and after cancer to actively manage both their physical and mental health during and after treatment” , said lead author Jennifer Brunet, Ph.D., of the University of Ottawa.

Dr. Brunet noted that many women undergoing chemotherapy for breast cancer do not remain sufficiently active and there are limited exercise programs tailored to their needs.

“To address this, we advocate for collaboration across sectors – academia, healthcare, fitness and community – to develop exercise programs specifically designed for women with breast cancer,” she said.

“These programs should be easy to adopt and widely implemented, making the benefits of exercise more accessible to all women facing the challenges of cancer treatment and recovery.”