Abstract
BACKGROUND: Physical inactivity and prolonged sitting are major risk factors for prediabetes and type 2 diabetes (T2DM). Despite this, individuals with prediabetes and T2DM often face challenges in maintaining adequate physical activity. The ENERGISED trial aimed to address this by using a mobile health (mHealth) intervention combining wearable Fitbit devices, just-in-time context-sensitive text messages (JITAI), and telephone counselling, tailored to the needs of individuals with prediabetes and T2DM. This study explored participants’ experiences with the intervention to inform future improvements and broader implementation. METHODS: A qualitative study was conducted using semi-structured telephone interviews with 27 participants (20 with T2DM and 7 with prediabetes, aged 42–80 years) from the intervention arm of the ENERGISED trial. Interviews explored motivations for participating in the ENERGISED program and factors influencing subsequent adherence, as well as barriers and motivations and facilitators in physical behaviour changes, e.g., increased physical activity and reduced sedentary time. Data were analysed using abductive thematic analysis to identify key themes related to the intervention’s components and participants’ behaviour changes. RESULTS: Two overarching themes were identified: (1) Motivations and facilitators to engaging with physical activity and the intervention, and (2) Barriers to engaging with physical activity and the intervention. Motivations were predominantly internal and health-driven, supported by intervention components, particularly the Fitbit device and telephone counselling, which enhanced self-monitoring, accountability, and adherence. Text messages showed mixed acceptability, with JITAI prompts to interrupt prolonged sitting perceived more positively than prompts to increase walking pace. The most prominent barriers were health-related limitations, adverse weather, work and time constraints, and technology-related difficulties. CONCLUSIONS: The ENERGISED program demonstrated that mHealth tools, particularly wearables and personalised support, can aid self-reported lifestyle changes in prediabetes and T2DM management. Refining just-in-time text messages to better align with participant needs could further enhance outcomes. These findings are key for improving future mHealth interventions to increase physical activity and reduce sedentary behaviour in individuals with prediabetes and T2DM. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-026-26668-y.