Using mobile health interventions to promote physical activity: a mixed methods study

Mobile technologies (e.g. mobile applications, wearable trackers) and online social networks have emerged as potential facilitators of physical activity. To date, few studies have examined the integration of these technologies in an intervention, users' perceptions about them, and their combined efficacy on physical activity. This study adopted a mixed method design within a pre-post, one-arm quasi-experiment to evaluate the efficacy and acceptability of a mobile social networking application, connected with a wearable tracker, to promote physical activity. Quantitative results were analyzed using descriptive and inferential statistics. Interviews and focus groups were conducted before and after the intervention to explore users' perspectives. Fifty-five participants were enrolled in the study (mean age=23.6 years, 50.1% female). Quantitative analysis revealed a non-statistically significant increase in average daily step count between baseline and 6 months (mean change = 14.5 steps/day, P = 0.98, 95% confidence interval [-1136.5, 1107.5]). Post-hoc subgroup analysis comparing the higher and lower physical activity groups at baseline showed that the latter had a statistically significantly higher increase in their daily step count (group difference in mean change from baseline to 6 months = 3025 steps per day, P = 0.008,95% confidence interval [837.9, 5211.8]. Qualitative analysis indicated users' preference for selfregulation techniques, social comparison with similar or existing connections, and personalization features. The study demonstrated the feasibility of a mobile social networking app, connected with a wearable tracker for physical activity promotion. A one-size-fits-all approach to behavior change was deemed insufficient by users, calling for the development of personalized interventions in future research.