A systematic review and meta-analysis of non-workplace interventions to reduce time spent sedentary in adults

Background: Sedentary behaviour has been the focus of considerable clinical, policy and research interest due to its detrimental effects on health and wellbeing. This systematic review aims to (1) develop a more precise description of different categories of interventions that aim to reduce sedentary time in adults by identifying specific components that form an intervention; (2) explore the effect of different categories of interventions in reducing time spent sedentary in adults. Methods: Ten electronic databases, websites of relevant organisations (e.g. the Sedentary Behaviour Research Network), and relevant reviews were searched. Inclusion criteria: Randomised controlled trials (RCTs), including cluster and randomised cross-over trials, in the adult population (clinical and non-clinical). Any study including a measure of sedentary behaviour was included even if reducing sedentary behaviour was not the primary aim. Exclusion criteria: Interventions delivered in schools, colleges, or workplaces; studies investigating the immediate effects of breaking up sitting time as part of a supervised (usually laboratory-based) intervention. Two review authors conducted data extraction and quality assessment (GRADE approach). Results: Searches identified 39,223 records, of which 85 studies met the inclusion criteria and were included in the review. Interventions shown to significantly reduce time spent sedentary were those which incorporated the provision of information, education, or support (advice/recommendations), in conjunction with either counselling (mean difference: -52.24 minutes/day; 95% CI: -85.37 to -19.10) or a form of structured/prescribed physical activity (standardised mean difference: -0.15; 95% CI: -0.23 to -0.07). However, this positive effect was not maintained at follow-up. No interventions were shown to break up prolonged sitting. Conclusions: This review presents a novel way of categorising interventions according to the types of components they comprised. There is evidence that interventions might be effective in reducing time spent sedentary immediately post-intervention. There were limited studies measuring sustained behaviour change.