This is a single-arm pre-post pilot study, to assess changes in weight, quality of life and cardiorespiratory fitness after a diet and physical activity intervention in breast cancer survivors and to asses possible relation between these changes.

Aim:

The present study assessed changes in weight, quality of life (QoL) and cardiorespiratory fitness (CRF) during a diet and physical activity (PA) intervention in breast cancer (BC) survivors and investigated the possible relation between these changes.

Methods:

The intervention of this 12-week single-arm pre-post pilot study involved group-based sessions: one-hour weekly diet sessions delivered by a dietician and 75-minute bi-weekly PA sessions of moderate-to-high intensity led by PA monitors. This intervention, designed to promote weight loss, targeted overweight/obese women who had completed treatment less than six months before recruitment. CRF and QoL were assessed before and after the intervention and compared using paired t-tests. Linear regression models, including CRF variables, weight change and participants' characteristics, were used to assess the independent association between change in CRF and change in QoL.

Inclusion Criteria:

• Female patients from the Catalan Institute of Oncology
• Aged 18 to 75
• Body mass index (BMI) of 25 kg•m-2 or more
• Completed chemotherapy and/or radiotherapy for breast cancer during the 6 months preceding recruitment

Exclusion Criteria:

• First cancer, tumours of stage IIIB and above
• Morbid obesity (BMI ≥40 kg•m-2)
• Any condition that could not permit to follow the diet and PA intervention offered