The importance of affective beliefs and attitudes in the theory of planned behavior: Predicting intention to increase physical activity

Standard theory of planned behavior (TPB) questions to elicit salient behavioral beliefs may elicit instrumental consequences of behavior, and overlook affective consequences. Two hundred thirteen English adults (35 to 75 years of age) completed a questionnaire that contained closed measures of TPB constructs, and open-ended questions that asked not only about advantages and disadvantages, but also what respondents would like or enjoy and dislike or hate about being more physically active. Beliefs elicited by affective questions were associated more strongly with a closed affective attitude scale. Beliefs elicited by instrumental questions were associated more strongly with a closed instrumental attitude scale. Closed measures of the standard TPB variables explained 48% of the variance in intention to increase physical activity, while affective attitude explained an additional 11% of the variance. Applications of the TPB should consider affective and not just instrumental determinants of behavior.