Some chemotherapy drugs (e.g., anthracyclines) are known to cause declines in heart health. Although these treatments are effective for the treatment of the patients’ breast cancer, some will experience substantial heart damage that may lead to heart failure and death. As these treatments are highly effective, there is a need to find ways to reduce the damaging effects while not interfering with its anticancer potential. The purpose of EXACT2.0 is to determine whether exercise can protect the hearts of females receiving anthracycline chemotherapy for breast cancer. Participants will be given a 6-month home-based aerobic exercise program (e.g. walking) to perform twice per week. This work will help determine whether exercise can be used in the future to minimize the structural damage of the heart caused by anthracycline chemotherapy.