Use of social-cognitive theories in the study of physical activity and fibromyalgia, self-efficacy theory and the theory of planned behaviour

Abstract

Using self-efficacy theory (Bandura, 1986, 1997) and the theory of planned behaviour (Ajzen, 1985, 1991) as theoretical frameworks, the primary objectives of the series of studies in this dissertation were to (a) determine the relationship between activity level, efficacy, and indices of well-being in Study 1; (b) identify the usefulness of the theory of planned behaviour, and in particular perceived behavioural control or self-efficacy, for predicting physical activity intentions and behaviour in Study 2; and (c) investigate an intervention designed to manipulate social cognitive constructs within the theory of planned behaviour in Study 3. All three studies examined individuals with Fibromyalgia (FM). FM is a chronic disease that is characterized by widespread pain and accompanying fatigue, which fluctuates over time. Previous literature has highlighted the importance of efficacy for functioning more effectively with this condition, however very little of this work has been guided by theory. Utilizing the framework of self-efficacy theory (Bandura, 1997) in Study 1, FM participants reported their efficacy for being physically active and for coping with their FM symptoms, as well as their physical activity levels and functional ability level. Both types of efficacy predicted physical activity frequency and functional ability status. Specifically, the more active FM individuals and those who functioned better on a daily basis had higher levels of efficacy or confidence in their ability to both be active and cope with their FM pain. This study provided the first examination of efficacy in relation to a frequency measure of physical activity and supports the physical activity literature findings for both healthy and symptomatic populations.

The purpose of Study 2 was to examine additional social cognitive predictors of physical activity frequency. The theory of planned behaviour (Ajzen, 1985) provided the framework to assess perceived behavioural control (efficacy) along with affective (attitude) and social (subjective norm) components for predicting physical activity intentions and behaviour. This prospective design revealed that physical activity intentions were predicted by perceived behavioural control, while both intentions and perceived behavioural control predicted physical activity behaviour. These results are supportive of the direct hypothesis of the TPB. While these results are again supportive of the general physical activity literature, the relative weaker roles of both attitude and subjective norm were somewhat surprising. In particular, the weaker role of attitude was inconsistent with past physical activity research both in healthy and diseased populations.

Study 3 attempted to further examine the importance of these three TPB variables for understanding physical activity and FM in an intervention-based design. Utilizing a group discussion format, attitudes, perceived behavioural control, and subjective norm towards physical activity were targeted within "positive" and "negative" conditions. The results revealed that this short-term intervention was effective at changing all three targeted variables. Specifically, at the post-manipulation measurement, FM individuals in the positive condition had significantly higher attitudes, perceived behavioural control, and subjective norm towards physical activity compared to the FM individuals in the negative condition.

Together, the results of this series of three studies support the importance of perceived behavioural control for understanding physical activity involvement in FM individuals. Additional social cognitive variables, including affective or social factors may also play an important role, however it is apparent that conceptual and measurement issues must be addressed in future research. Utilizing a strong theoretical framework will aid the progression of FM ad physical activity research and will ultimately enhance future interventions.