More In Action: Digital innovations in measuring and promoting physical activity in older adults

Abstract

Physical inactivity among older adults is a multifaceted public health challenge with profound implications for healthcare systems, chronic disease burden, and overall quality of life. However, this challenge also presents an opportunity to leverage digital health interventions that are evidence-based, personalized, and empowering. This thesis advances the field by exploring innovative strategies to promote physical activity (PA) among older adults through a multidimensional approach integrating behavioral science, technology, and preventive healthcare frameworks.

This research unfolds into three parts. Part I introduces a multidimensional PA assessment framework, employing ecological momentary assessment (EMA) and wearable sensors to capture real-time movement patterns and psychological determinants among 108 community-dwelling older adults. Findings indicate that PA levels peak at midday, decline toward the evening, and predominantly consist of low-to-moderate intensity movement. The study further highlights the critical role of motivation, context, and self-efficacy in shaping PA behavior, reinforcing the notion that PA is not merely a physiological process but a complex behavioral construct. Part II examines the development and feasibility of the MIA app, a mobile health intervention co-designed with older adults. Unlike conventional PA interventions, MIA is designed to optimize engagement through an iterative, user- centered process, integrating behavior change techniques, social interaction, and personalized recommendations. Feasibility outcomes demonstrate high usability, strong user satisfaction, and consistent adherence, emphasizing the importance of aligning digital interventions with the needs and preferences of end-users to facilitate sustainable behavior change. Part III situates PA promotion within a broader preventive healthcare framework, emphasizing the role of digital health technologies in mitigating health disparities and fostering active, socially connected communities.

By bridging the gap between research and practice, science and implementation, this thesis underscores the potential of technology-driven interventions in enhancing the health and well-being of older adults, ultimately fostering a more resilient and connected society.