Abstract
University is a vulnerable period for discontinuing regular physical activity, which can have implications for individuals' physical and psychological health (Bray & Born, 2010). Accordingly, it is imperative to develop and implement cost and time-effective interventions to mitigate the consequences of this transition. Mental contrasting is a self-regulatory strategy that involves imagining the greatest outcome associated with achieving a desired goal while also considering the most critical obstacle for attaining that same goal (Oettingen & Gollwitzer, 2010). Intervention research has shown that mental contrasting can be taught in a cost- and time-effective way, affecting numerous health behaviours including physical activity (Oettingen, 2012). Drawing from diverse theoretical perspectives, recent meta-analytic evidence suggests that affective judgements (e.g., enjoyable-unenjoyable) exert greater influence on physical activity behaviours than instrumental judgements (e.g., useful-useless; Rhodes, Fiala, & Conner, 2009). The present study utilized mental contrasting as a means of targeting affective judgements, through intervention, in order to bolster physical activity promotion efforts. 110 inactive, female, university students were randomly assigned to an affective, instrumental or standard mental contrasting intervention. Assessments were conducted at baseline, and 4-weeks post intervention. After controlling for baseline levels, participants in the affective mental contrasting condition displayed higher moderate-to-vigorous physical activity (MVPA) than those in the instrumental or standard comparison conditions, F(2, 90) = 3.14, p < .05, ηp2 = 0.065. Overall, affective mental contrasting may help inactive, female students increase activity or attenuate declining levels of MVPA that typically occurs during university.Acknowledgments: This research was supported by a graduate scholarship awarded to Geralyn Ruissen by the Canadian Institute of Health Research.