Chemotherapy forms a significant part of many breast cancer patient's treatment and is associated with various common, known adverse effects. For the last few decades, physical activity has been emerging as a viable intervention to help many of these adverse effects. The study will determine if the provision of a 12-week tailored walking programme, provided alongside a home-based exercise prescription from a cancer doctor results in improved levels of physical activity and quality of life in patients with breast cancer undergoing chemotherapy.

Background Breast cancer is the most common cancer in females, with over 85% of women surviving their disease for 5 years or more. Chemotherapy forms a significant part of many patient's treatment and is associated with various common, well-characterised adverse effects. For the last few decades, physical activity has been emerging as a viable intervention to help many of the adverse effects of chemotherapy. Studies looking at patient's preferences have shown that the majority preferred walking, moderate-intensity, home-based exercise. Previous small studies have shown that cancer doctors have considerable influence on exercise behaviour; a simple recommendation significantly increased the activity levels of newly diagnosed breast cancer patients commencing treatment. A further question in the study will also assess the effect of exercise on markers of chronic inflammation in the blood. Exercise is known to reduce inflammation and this may play a significant role in cancer.

Method The study will determine if the provision of a 12-week tailored walking programme, provided alongside a home-based exercise prescription from a cancer doctor results in improved levels of physical activity in patients with breast cancer undergoing chemotherapy. Secondary objectives will assess patient-reported activity, quality-of-life, completion rates of chemotherapy, cognitive function, anxiety and depression levels, body composition as well as exploring the role of the effects on specific markers of chronic inflammation in the blood.

The investigators will recruit 100 patients from LRI undergoing chemotherapy for breast cancer. Participants will be allocated to either the intervention or a standard care group in this study. Those in the intervention group will receive the walking programme with various motivational strategies incorporated as well as a discussion on the benefits of exercise and a prescription from the cancer team. Those in the standard care will not receive the intervention material. All women will wear wrist accelerometers (to measure activity levels) before and after the 12-week period and complete assessments at these points (as well as a further follow up assessment at 6 months). Assessments will include study questionnaires, cognitive testing, measurements of body fat and blood tests.

Potential impact The investigators aim to show that the intervention will result in significantly improved levels of physical activity, as well as improved quality of life and improvements in other secondary outcome measures. They also predict that the intervention will result in a significant lowering of inflammatory marker concentration when compared to standard care. The study will provide an important addition to the evidence that exists for cancer teams to encourage patients and survivors to meet national physical activity guidelines. In the longer term, the intervention being tested in the proposed study has the potential to be an inexpensive and sustainable addition to the standard care provided to cancer patients and this will hopefully lead to a larger-scale national study.

Inclusion Criteria:

• Written informed consent prior to admission to the study.
• Age 18-75 years of age.
• Able to read and speak English.
• Not currently meeting national guidelines for exercise (i.e. <150mins moderate intensity exercise on 5 or more days per week).
• Histologically confirmed diagnosis of primary breast malignancy (GROUP 1), OR Histological or radiological confirmation of advanced/metastatic breast malignancy (GROUP 2).
• Due to commence (or within 3 weeks of commencing) neo-adjuvant or adjuvant systemic chemotherapy for breast malignancy (GROUP 1), OR Due to commence (or within 3 weeks of commencing) any line of palliative systemic chemotherapy for breast malignancy (GROUP 2).
• ECOG Performance Status 0-2.
• Able (in investigator's opinion) to be able to comply with all study requirements and exercise prescription.

Exclusion Criteria:

• Any severe or uncontrolled medical conditions.
• Any unstable or uncontrolled cardiopulmonary illness.
• Recent Myocardial Infarction (<6months)
• Implanted Cardiac defibrillator.
• Uncontrolled Hypertension
• Pregnancy or <12 weeks post-partum.
• Life expectancy <3 months.
• Prior history of neurological or psychiatric disorder, which could cause cognitive deficits.
• Current or planned enrolment in structured exercise or weight loss programme.
• Injury, disability or symptoms preventing compliance with exercise prescription.
• Psychological, sociological or geographical conditions that do not permit compliance with the study protocol or exercise prescription.