The Norwegian Healthy Life Centre Study: A pragmatic RCT of physical activity in primary care

Aims: The aim of this study was to evaluate the effect of behaviour change interventions at Norwegian Healthy Life Centres (HLCs) on participants' moderate to vigorous intensity physical activity (MVPA) six months after baseline. We also explore predictors of change in MVPA, and if level of education and MVPA at baseline modify the effect. Methods: A randomised controlled trial with inclusion criteria age > 18 years and ability to participate in group-based physical activity. Participants were randomised to either behaviour change interventions or a waiting list (control). Objective recordings of physical activity were the main outcome, analysed with simple and multiple linear regression. Results: We recruited 118 participants from six HLCs. Participants with mental, musculoskeletal, or chronic somatic disease were more likely to drop out. We revealed no differences in MVPA or sedentary time between the groups. Types of motivation or several characteristics of disadvantage at baseline could not explain changes in MVPA. Across both groups, 83% achieved the recommended 150 minutes of MVPA per week, and participants with a lower level of education were less likely to improve. Participants in the intervention group who were least active at baseline significantly increased their MVPA. Conclusions: The study revealed that the intervention had no short-term effect on time spent on MVPA or sedentary. This study does not support a strong emphasis on behaviour change on an individual level as a way of targeting general health and risk reduction at a population level. Although less active people benefitted more from the HLC intervention, the intervention was unable to counteract widening of inequity across educational groups.