This study investigated the moderating influence of the five-factor model of personality (FFM) on the theory of planned behavior (TPB) in the exercise domain. Although an analysis of all possible moderation effects was conducted, it was hypothesized that high extraversion (E) and conscientiousness (C) individuals would demonstrate significantly stronger relationships between intentions and exercise behavior than those low in E and C. Conversely, it was expected that high neuroticism (N) individuals would show a significantly weaker relationship between intention and exercise behavior than those low in N. A total of 300 undergraduate students completed measures of the FFM, TPB, and a 2-week follow-up of exercise behavior. Two-group structural equation models of the TPB were created using a median split for each personality trait. Overall, 5 significant (p < .05) moderating effects were found. Specifically, N was found to moderate the effect of subjective norm on intention. E also moderated the effects of subjective norm on intention as well as intention on behavior. C moderated the effects of affective attitude on intention and intention on behavior. Theorized influences for the presence or absence of personality moderators are discussed. The results generally support the possibility of personality being a moderator of the TPB but highlight the need for future research and replication.
Ryan Rhodes is with the School of Physical Education, Univ. of Victoria, Victoria, BC, Canada V8W 3P1; Kerry Courneya is with the Faculty of Physical Education, and Leslie Hayduk is with the Dept. of Sociology, Univ. of Alberta, Edmonton, AB, Canada T6G 2H4.