Promoting physical activity in a workplace setting: A randomized control group study of stage-matched interventions

According to stage theories, theory-based interventions promoting physical activity can be tailored to the stages of change. Stage theories assume that different social-cognitive variables are important at different stages to induce subsequent behavior change processes. The aim of this study was to evaluate stage-specific effects of stage-matched interventions targeting physical activity and its social-cognitive predictors in a workplace setting. 839 employees of a large-scale company were randomized to a stage-matched intervention or a stage-unspecific standard-care intervention. Four weeks later, goal-setting, planning and physical activity were reassessed. Data analyses were performed with repeated-measures ANOVAs. Compared to a control condition, stage-matched interventions were superior in increasing stage-specific outcomes. Stage-matched interventions appeared superior to standard-care interventions. In addition to behavior, changes in social-cognitive variables may be considered when evaluating interventions.