Digital future-self interventions to promote physical activity: perspectives of minimally active middle-aged and older adults

Abstract Objectives Promoting physical activity is crucial for reducing disease risk and improving overall health. This study targeted minimally active individuals aged 45 and older. It aimed to inform the design of effective digital tools for promoting physical activity by exploring their perspectives on two prototype future-self interventions: a mental imagery and an avatar-based approach. Methods Three online focus groups (n=10, age range 47–70) were conducted to assess the comprehensibility, acceptability, anticipated effectiveness and preferred formatting of both prototypes. Results The prototype for both interventions was deemed comprehensible, but the mental imagery approach was found more appealing and anticipated to be more effective in encouraging physical activity. Participants highlighted the importance of user-friendly, visually engaging, and customizable features in the intervention. Conclusions Based on the insights, we recommend prioritizing mental imagery future-self interventions with clear default settings – such as future-self task order – while allowing for personalization to optimize user engagement and effectiveness. Findings from this study provide actionable guidance for developing digital physical activity interventions tailored to minimally active middle-aged to older adults.