Aerobic Exercise and Cognitive Functioning in Breast Cancer

In Canada, approximately 68 women are diagnosed with breast cancer every day. Chemotherapy-related cognitive changes (CRCC) are reported by up to 75% of breast cancer survivors during treatment and symptoms persist in 35% of survivors after treatment. Women report that CRCC negatively impacts their everyday functioning and substantially reduces their overall quality of life. Effective clinical interventions to manage CRCC are elusive. As a result, breast cancer survivors typically receive little to no advice on how to prevent or manage CRCC. Aerobic exercise is a type of physical activity that uses large muscle groups, is rhythmic in nature, and can be sustained for at least 10 minutes (e.g., walking, jogging, indoor cycling). It has been associated with improved quality of life in breast cancer survivors. It also holds great promise as an intervention to prevent or mitigate CRCC. However, there is limited evidence from experimental studies to confirm this. Therefore, the primary aim of this trial is to evaluate the impact of a supervised aerobic exercise intervention on CRCC in women diagnosed with early-stage breast cancer. Recruited women will be randomized into one of two groups: (1) aerobic exercise during chemotherapy, or (2) usual care during chemotherapy and the aerobic exercise post-chemotherapy (i.e., wait-list control group). This study will test several novel hypotheses, including whether exercise during chemotherapy can prevent and/or mitigate CRCC and its negative impact on quality of life among women with breast cancer, and whether the timing of the exercise intervention matters (i.e., exercise during versus after chemotherapy). The results of this study aim to address the concerns of women affected by CRCC who are currently lacking available evidence-based treatment options, as well as oncology care providers' need to have options to recommend to their patients to prevent or manage CRCC.