The present study aimed to test the efficacy of rationally framed and affectively framed audiovisual media messages on psychological determinants of physical activity. It was hypothesized that affectively framed messages would have greater effects on implicit attitudes toward exercise and that the need for cognition of the participants would serve as a moderating variable for the ability of the two messaging styles to change explicit instrumental and affective attitudes toward physical activity.

To test the hypotheses of this study, 85 participants were randomly allocated to one of three messaging conditions, affectively framed (n = 28), rationally framed (n = 29), or control messages (n = 28). In each group, participants were pretested and then received a media exposure each day for one week, which contained these messaging styles (control group participants received media exposures with physical activity-void content). A series of factorial ANOVAs were conducted to detect differences between groups over time for the 76 participants who completed the postintervention assessments.

Overall, there was no group by time interaction for any of the dependent variables (explicit and implicit attitudes toward physical activity, situated decisions to exercise, or self-reported physical activity level). Increased media exposure and a sample affording greater statistical power may be necessary to determine any differences in treatment effects between rationally and affectively framed messaging styles.