Benefits of nature-based walking for breast cancer survivors

INTRODUCTION: Physical activity (PA) promotes significant physical and psychosocial benefits for breast cancer survivors. While evidence exists regarding recommendations for the frequency, duration and intensity of exercise that optimise PA benefits for cancer survivors, the role of the environment in achieving optimal outcomes has yet to be determined. This paper presents a protocol for a clinical trial to evaluate the feasibility of a 3-month nature-based walking programme for breast cancer survivors. Secondary outcomes assessed include the impact of the intervention on fitness, quality of life outcomes, and biomarkers of ageing and inflammation. METHODS AND ANALYSIS: The trial is a 12-week single-arm pilot study. Twenty female breast cancer survivors will engage in a supervised moderate intensity walking intervention in small groups in a nature reserve for 50 minutes three times per week. Data will be collected at baseline and end of study, and include assessment of inflammatory cytokines and anti-inflammatory myokines (TNF-α, IL-1ß, IL-6, CRP, TGF-ß, IL-10, IL-13), as well as ageing (DNA methylation, ageing genes) biomarkers; surveys (Patient-Reported Outcomes Measurement Information System-29, Functional Assessment of Cancer Therapy-General, Post-Traumatic Growth Inventory); and fitness assessments (6 min Walk Test, Grip-Strength, One Repetition-Maximum Leg Press). Participants will also complete weekly surveys assessing social support and participate in an exit interview. This is an important first step for future research on the influence of exercise environment on cancer survivor PA outcomes. ETHICS AND DISSEMINATION: This study was approved by the Cedars Sinai Medical Center Institutional Review Board (IIT2020-20). Findings will be disseminated through academic manuscripts, conferences, and community presentations. TRIAL REGISTRATION NUMBER: NCT04896580.