Purpose: While wearable self-trackers (WSTs) are marketed for self-care, fitness, and health improvement, emerging evidence highlights the potential for negative impacts. This paper explores the use of WSTs adopting a practice theory approach to unravel the contextual and individual factors that shape different patterns of WST usage and consumer vulnerability to harm. Methodology: A qualitative study using semi-structured interviews and visual stimuli of self-tracking data was conducted with 30 Fitbit users. Data were analysed using thematic analysis, followed by idiographic and cross-case analysis to map usage patterns and reflexivity. Findings: Three distinct WST usage patterns were identified: light, fluctuant, and intensive. The study finds that reflexivity on physical activity identity and goals plays a key role in shaping these patterns, with users' critical capacity in identity transitions emerging as a key underpinning factor in vulnerability to harm. Originality: This research focuses on the context of self-tracking and extends existing literature on digital vulnerability, defined as a state in which people are at risk of harm due to external conditions and personal states and circumstances that significantly inhibit their agency in practices involving digital technologies. It reveals differentiated patterns of WST use and the role of identities and identity work in shaping WST use and users’ vulnerability to potential harms. Practical and social implications: To mitigate potential harms and promote healthier self-tracking practices, the study suggests the application of safe design, transparency, and accountability principles, accounting for individual goals and experience levels, and tailored guidance and educational support for users.
Bakr et al. (Sat,) studied this question.