RESUMEN
Outdoor walking groups are nature-based interventions (NBIs) that promote health and wellbeing by modifying individual behaviour. The challenges of such NBIs include the motivation of inactive adults to participate and measurement issues. This feasibility study investigates a 12-week group outdoor health walk (GOHW) incorporating activity trackers and use of a holistic health and wellbeing measure, the Self-sasessment of Change (SAC) scale. A mixed methods design explored participant recruitment and retention, programme delivery, and measures of physical activity and health and wellbeing. Walker data included: pre-post questionnaires, daily step counts, and interviews. Programme delivery information included: weekly checklists, staff reflections, stakeholder meeting minutes, and a report. Thirteen adults (age 63-81, 76% female) joined and completed the activity tracker GOHW. Activity trackers motivated walkers to join and be more active but complicated programme delivery. Activity trackers allowed the quantification of physical activity and the SAC health and wellbeing measure was easy to use. By week 12, all participants met national physical activity guidelines. Clinically relevant changes on the SAC scale included: sleeping well, experiencing vibrant senses, and feeling energised, focused, joyful, calm and whole. Results illustrate the feasibility of using activity trackers to motivate engagement in and provide a measure of physical activity from GOHWs. The SAC scale offers a promising measure for nature-health research. A conceptual model is provided for the development of future large-scale studies of NBIs, such as group outdoor health walks.