Abstract
Social cognitive theory posits that self-efficacy influences behaviour when the necessary skills and incentives are present (Bandura, 1986). Exercise motivation research has focussed on self-efficacy with limited attention to outcome expectations (OE). One complication of assessing OE, stemming from expectancy-value theory, is the determination of whether likelihood or desirability more strongly predicts intention. The purpose of this study was to evaluate OE groupings and the distinction between likelihood and desirability of exercise OE in relation to intentions. A sample of 263 undergraduate students indicated the likelihood and desirability of 51 exercise outcomes, exercise intention, and exercise self-efficacy. Exploratory factor analysis using principal axis factoring with Oblimin rotation and Kaiser normalization yielded 8 likelihood and 11 desirability factors which were interpretable. An aggregate score was created for each factor and data were analyzed using hierarchical regression. Self-efficacy strongly predicted exercise intention, and desirability and likelihood were independently related to intention, regardless of the order in which they were entered. Likelihood and desirability of effort enjoyment (beta = .190 and .135 respectively), and desirability of physical health (beta=.154) were the only significant predictors of exercise intention in addition to self-efficacy (beta.499), final R2=.532. These findings indicate that likelihood and desirability explain unique variance in exercise intention and should be considered individually. The finding that likelihood and desirability appear to create interpretable factor structures when considered separately but not when considered together further supports their distinction. Future research would aim to test the robustness of the findings across various samples.Acknowledgments: CIHR