The REgulate your SItting Time (RESIT) is a tailored intervention targeting reductions and breaks in sitting in adults with type 2 diabetes mellitus (T2DM). A feasibility trial of RESIT had been conducted and the purpose of this paper is to report findings from the process evaluation.

A mixed-methods process evaluation within a randomised controlled feasibility trial.

The study was conducted remotely in the community.

Ambulatory individuals with T2DM aged 18–85 years.

A tailored intervention comprising an online education session, regular health coaching and technology for self-monitoring behaviour and prompting breaks in sitting.

Questionnaires (intervention participants n=22 at both 3 and 6 months; control participants n=21 at 3 months, n=29 at 6 months) and interviews (n=30, with n=13 intervention participants, n=12 control participants, n=5 health coaches) to assess perceptions of the intervention components, strategies and barriers for sitting less, the role of the study evaluation measures, and reasons for taking part.

The trial operated a largely successful online education element for those in the intervention group (82% completion; ≥76% engagement in individual educational elements). There was good use of self-monitoring and prompt technology (apps and wearables) with 73% of participants reporting using these at 6 months. Health coaching had high engagement and was perceived as enjoyable and useful. Data revealed strategies used for behaviour change (eg, active functional tasks) alongside barriers to change (eg, restrictions at work). There were also potential behavioural influences from the study evaluation measures (eg, activity measures increasing awareness and execution of behaviours) for both intervention and control participants.

A comprehensive process evaluation identified successful intervention elements (ie, online education, health coaching, wearables and smartphone apps) alongside strategies and barriers to behaviour change. These findings can inform future sedentary behaviour interventions for adults with T2DM and a definitive randomised controlled trial evaluating RESIT.

ISRCTN14832389.