Structural Equation Modeling Supports Complex Interrelationships Between Personality, Outcome Expectations, Barriers, And Physical Activity

BACKGROUND: Evidence supports relationships between physical activity (PA) and personality. Theory suggests that these relationships work through intermediary variables often targeted by behavioral PA interventions. Understanding how personality influences PA through relevant intermediary variables may explain variability of intervention effects and inform new approaches. Outcome expectations (EXP) and barriers (BAR) for habitual PA are consistently related to PA, but it is unclear how these relationships are influenced by personality traits. AIMS: This study explored the postulates that (1) traits moderate relationships between EXP/BAR and PA and (2) EXP/BAR mediate relationships between traits and PA. METHODS: Traits, EXP, BAR, and PA were measured by self-report in a sample (n = 346) of college women. Structural equation models were specified to test moderation of relationships between EXP/BAR and PA by traits. Significant moderated relationships were modeled simultaneously with all trait, EXP and BAR variables as predictors of PA. Traits were also modeled as predictors of EXP/BAR for a test of mediation in the final model. Traits were allowed to correlate freely, as were EXP/BAR. RESULTS: The final model (R2 = .225) demonstrated acceptable fit. Neuroticism (β = .65; p < .001), EXP psychological benefit (β = .40; p < .05), EXP fun (β = .13; p < .05), BAR effort (β = -.271; p < .001) and BAR health limitations (β = .19; p = .001) independently predicted PA. The relationship between PA and EXP psychological benefit was moderated by neuroticism (β = -.72; p = .02). Extraversion, neuroticism, and conscientiousness had multiple direct effects on EXP/BAR. Indirect effects of conscientiousness and extraversion were transferred through BAR effort (β = .08; p < .01), and BAR health limitations (β = .03; p < .05), respectively. CONCLUSION: Personality traits exert some of their influence on PA through expectations and barriers. Effects of Conscientiousness and Extraversion were fully mediated by BAR effort and BAR health limitations, respectively. Relationships between expected psychological benefits and PA were stronger for those with lower vs higher neuroticism. Effects may explain observed variability in efforts to increase PA. Results can inform personality-focused adaptations to current approaches. Supported by: Research Initiation Grant, University Research Services and Administration, Georgia State Univeristy