“Follow the Whistle: Physical Activity Is Calling You”: Evaluation of Implementation and Impact of a Portuguese Nationwide Mass Media Campaign to Promote Physical Activity

Abstract

To raise perceived capability (C), opportunity (O) and motivation (M) for physical activity (PA) behaviour (B) among adults, the Portuguese Directorate-General of Health developed a mass media campaign named “Follow the Whistle”, based on behaviour change theory and social marketing principles. Comprehensive formative and process evaluation suggests this media-led campaign used best-practice principles. The campaign adopted a population-wide approach, had clear behavioural goals, and clear multi-strategy implementation. We assessed campaign awareness and initial impact using pre (n = 878, 57% women) and post-campaign (n = 1319, 58% women) independent adult population samples via an online questionnaire, comprising socio-demographic factors, campaign awareness and recall, and psychosocial and behavioural measures linked to the COM-B model. PA was assessed with IPAQ and the Activity Choice Index. The post-campaign recall was typical of levels following national campaigns (24%). Post-campaign measures were higher for key theory-based targets (all p < 0.05), namely self-efficacy, perceived opportunities to be more active and intrinsic motivation. The impact on social norms and self-efficacy was moderated by campaign awareness. Concerning PA, effects were found for vigorous activity (p < 0.01), but not for incidental activity. Overall the campaign impacted key theory-based intermediate outcomes, but did not influence incidental activity, which highlights the need for sustained and repeated campaign efforts.