Effects of a workplace physical activity intervention on cognitive determinants of physical activity: a randomized controlled trial.

The present randomized controlled trial evaluated if a workplace physical activity (PA) program that comprises both a PA component and a psychological coaching component (PA + C) is more effective in changing cognitive determinants of PA than a PA program without coaching component. Design: N = 213 employees were cluster-randomly assigned to two groups: the PA + C group received the MoVo-work intervention, combining a psychological coaching component and a PA component. The PA group received the PA component without psychological coaching. Main Outcome Measures: Strength of goal intention, self-efficacy, outcome expectations, action planning and barrier management were assessed at five time points (before and at the end of the intervention, as well as 6 weeks, 6 months and 12 months after the intervention). Results: After six weeks and one year, respectively, the PA + C group showed significantly higher goal intentions (p = .018) and self-efficacy beliefs (p = .006) than the PA group; and, at a descriptive level, a clear tendency towards better barrier management. Conclusions: The results indicate that a workplace PA program, including psychological coaching, may partially improve the effects of a pure PA program on critical motivational and volitional determinants of PA behavioural change among employees.