Mutrie, N., University of Glasgow, United Kingdom
Despite a high proportion of individuals believing in the efficacy of physical activity for obtaining and promoting good health, sedentary behaviour is prevalent in most societies. Understanding this gap between beliefs and behaviour represents a theoretical and practical challenge. Exercise psychology has adapted theories of behaviour change from social- cognitive, behavioural and health psychology to help explain and predict exercise behaviour. This presentation focuses on two key theories of exercise behaviour. These are The Theory of Planned Behaviour (Ajzen, 1988) and The Transtheoretical Model of Behaviour Change (Prochaska & DiClemente, 1983). The criteria for selection of these two models were 'frequency of citation' and research support in exercise intervention studies during the last ten years. Examples of research into physical activity behaviour change using these two models will be provided and the strengths and weaknesses of each model will be summarized. One main weakness of these theories is that they isolate the individual, and do not account for an environmental perspective. Other approaches to understanding behaviour change in physical activity, like the ecological model (Sallis & Owen, 1999) take a broader view, seeing the individual as one component part of a complex interaction between person and environment. While some progress has been made in recent years in terms of understanding physical activity behaviour from a theoretical perspective (Biddle & Nigg, 2000), there is still a need to develop a comprehensive theory of exercise behaviour change.