Remotely delivered support to promote physical activity behaviour change for women aged 50 years and over: study protocol for the Active Women over 50 hybrid type I effectiveness-implementation randomised controlled trial

Abstract Background Physical activity has health benefits but women in midlife years often face complex challenges to regular participation and could benefit from targeted support. The pilot-tested Active Women over 50 behaviour change program, was acceptable and feasible for supporting choice-based physical activity among women aged 50 years and over. This trial aims to establish the impact of the remotely-delivered Active Women over 50 program on physical activity among women aged 50 years and over compared with a waitlist control group. Methods This hybrid type I effectiveness-implementation randomised controlled trial ( n = 1000) will be conducted among community-dwelling women aged 50 years and over across NSW Australia, half living in rural/regional areas. Participants will set two physical activity SMART goals with a health coach and then be randomised to receive the Active Women over 50 program, or to a waitlist control group. The Active Women over 50 program will include (1) two empowerment-focused telephone health coaching sessions; (2) behaviour-change messages delivered by email or SMS text as preferred; (3) program-specific website containing information, tips and strategies and inspirational peer stories; and (4) private moderated Facebook group. The control group will be waitlisted to receive the Active Women over 50 program 6 months post-randomisation. The primary outcome will be average daily steps measured with the ActiGraph accelerometer at baseline and 6-months post-randomisation. Secondary outcomes include device-measured and self-reported physical activity, falls, quality of life, action and coping planning, process and implementation and scalability measures, and health utilisation. All analyses will be pre-planned and conducted while blinded to group allocation and will consider participant and geographical characteristics. An economic analysis will estimate cost-effectiveness and cost-utility of the intervention compared to no intervention. Discussion This hybrid type 1 effectiveness-implementation trial testing a flexible, remotely-delivered behaviour change intervention designed with consumer input will establish the impact on physical activity among women aged 50 + years living across diverse geographical settings. The trial design will also collect secondary implementation, scalability and cost outcomes to provide important information to stakeholder groups such as community groups, professionals, policymakers, funding bodies. Trial registration Australian New Zealand Clinical Trials Registry, ACTRN12624000026527, https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12624000026527 . Prospective registration date: 12 January 2024.