Title page

Abstract

This study examines whether a community-based physical activity intervention influenced movement in stages of change in physical activity in an adult population, whether any such effect was mediated by psychosocial influences, and whether any such mediations were moderated by socio-demographic or anthropometric factors. The three year long pseudoexperimental intervention (intervention; n= 616, mean age= 49.4 ± 9.9 years, control; n= 565, mean age= 49.1 ± 9.0 years) included physical activity, communication, environmental and participatory components. Stages of change in physical activity and potential psychosocial mediators were assessed by questionnaires. Regression analyses revealed a significant favourable intervention effect on stages of change, partially mediated by enhanced support from family, perceived control, and physical activity identity. No moderation effects by gender, age, ethnicity, education or BMI were observed. Support from family, perceived control, and identity might be important intervention target points for inducing forward movement in the stages of change in physical activity, regardless of socio-demographic and anthropometric background factors.