Author:

Abstract:

Wearable activity tracking systems have the potential to support older adults to remain or become more physically active, and physical activity plays an important role in promoting health and maintaining a high quality of life in late life. Yet, we do not have a good understanding of older adults' relation with physical activity or wearable activity tracking systems, and what kind of designs meet their needs. In our work, we used a mixed-methods, humancentred approach to contribute to a better understanding of this, involving older adults in focus groups, interviews, and online surveys. First, we explored what kind of wearable activity trackers exist to track older adults' physical activity. Then, we examined how older adults perceive physical activity and wearable activity tracking, and what barriers they encounter while being physically active or using such systems. Next, we investigated what visualisations of physical activity data appeal to older adults, and how they perceive them when physical performance or pleasure is emphasised. Finally, we explored flexible tracking as a way to make activity tracking accessible to older adults who use mobility aids. Overall, we found that current efforts by industry and academia focus on leveraging wearable activity trackers in a medical context, where they are used to supervise older adults, rather than to support them to be physically active. Furthermore, older adults are rarely involved in the design process of activity trackers that are geared towards them. As a result, we identified gaps in our knowledge on older adults and their relation with physical activity, wearable activity trackers, and visualisations of physical activity data. Our findings suggest that older adults find it important to retain agency in when and how physically active they are and what kind of activities they want to engage in. At the same time, they have complex reasons for being (in)active and can be hindered by barriers that prevent them from being physically active with regard to physical discomfort or restrictions of the built environment. Moreover, wearable activity tracking systems are an emotional technology that can be a source of anxiety when it reminds older adults of medical tracking. Systems should aim to offer features that interest older adults without overwhelming them, and without pressuring them to perform. We found that this applies to wearable activity trackers and visualisations of physical activity data alike, and is affected by older adults' lived experience. Furthermore, older persons have a wide variety of wishes and needs regarding visualisations, in which both highlighting the pleasure of the activity and informing them on their performance can be relevant, depending on older adults' habits and preferences. Guided by our findings, we explored how flexible tracking can address barriers older adults face when they use mobility aids, and provide implications for design to facilitate the creation of wearable activity tracking systems for older adults. In sum, this doctoral research contributes detailed insight into older adults' lived experience of physical activity and reasons for being physically (in)active. On this basis, it formulates implications for the design of wearable activity tracking systems for older adults that align with their preferences. Most importantly, systems should aim to support older adults with features and visualisations that are useful and meaningful, be mindful of barriers they may encounter, acknowledge the role of pleasure in addition to that of performance of physical activities, and be respectful of older adults' agency.