Sit-stand desks as a strategy to reduce sitting and increase standing and physical activity in office-based employees: a pilot RCT and process evaluation of a multicomponent workplace intervention intervention

Abstract

Current UK public health policy and research identifies potential health risks of physical inactivity and high levels of sitting. This is a particularly pertinent issue for office workers, who spend, on average, over two-thirds of the work day sitting. This thesis reports on the design and evaluation of a multicomponent sit-stand desk intervention, delivered within two not-for-profit office-based organisations in London, England. A mixed method study design was employed. A pilot randomised controlled trial examined the efficacy of the intervention on reducing sitting and increasing standing and physical activity, using wearable monitors to measure outcome variables at baseline, and at four additional timepoints up to 12-months following the onset of the intervention. A process evaluation, including in-depth qualitative interviews and participant observation, investigated the processes that influenced the feasibility, acceptability and efficacy of the intervention. Mixed-model ANOVA indicated that the intervention reduced workplace sitting, on average, by 38 minutes, however there was no significant influence on workplace physical activity, or any of the outcome variables across the whole day. The process evaluation revealed that discourses surrounding employee health and organisational effectiveness, and employees’ health-focused occupational identities increased the acceptability of sit-stand desk provision, whereas monetary concerns, a centralised organisational structure and incompatibility of the sit-stand desks with the workplace environment negatively influenced implementation feasibility. The sit-stand desk design, expectations and outcomes related to health and productivity, and the organisational culture and interpersonal relationships positively and negatively influenced sit-stand desk experience to differing degrees between participants. Mixed method analyses of outcome and process data illustrated the potential for integrating findings to enhance understanding of ‘what works’ within behavioural intervention research. Sit-stand desks are not a one-size-fits-all solution to reducing sitting and increasing physical activity, however, they should be available to office-based employees as part of a wider workplace health strategy.