An evaluation of an intervention designed to help inactive adults become more active with a peer mentoring component: a protocol for a cluster randomised feasibility trial of the Move for Life programme

BACKGROUND: There is overwhelming evidence to support the promotion of physical activity in adults in terms of benefits to well-being, physical and mental health. Physical activity guidelines suggest that adults should accumulate at least 150 min of moderate to vigorous physical activity per week. In Ireland, the majority of adults do not achieve these guidelines, with costs to health and economy. ‘Move for Life’ (MFL) employs behavioural change techniques delivered by an instructor and peer mentor, using a train-the-trainer (cascade) model. This study will conduct a feasibility cluster randomised controlled trial of the MFL intervention for modifying physical activity behaviours in inactive adults aged 45 years and older. METHODS: The trial is set in eight Local Sports Partnership (LSP) hubs that have structured physical activity programmes. The hubs are the units of randomisation (clusters), and individuals are the units of analysis (participants). Eligible participants will contact one of the hubs, with each hub running four physical activity programmes. Each programme requires between 12–15 inactive adults, resulting in 48–60 participants per hub. Allowing for 20% dropout rate, an additional 96 people will be recruited giving a maximum sample of 576. The hub will be randomised: true control, usual programme or MFL intervention. The true control group will be given information about physical activity but will not be included in a programme for the duration of the trial; the intervention will involve the instructor training one (or more) of the participants to be a peer mentor using an educational toolkit; and usual care groups will have physical activity classes delivered as normal. Baseline data will collect physical activity measures and follow-up measurements will be obtained at 3 and 6 months. All participants will be asked to wear a device for measuring activity on the thigh (activPAL) for 7 days before commencing the programme and at 3 and 6 months. The primary objective of the study is to investigate if it is feasible to deliver the intervention and collect data on moderate to vigorous physical activity (MVPA) on all participants, thereby providing valuable information to guide sample size calculation for a future, more definitive trial. TRIAL REGISTRATION NUMBER: ISRCTN11235176 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40814-019-0473-y) contains supplementary material, which is available to authorized users.