Medicina Comunitária e Educação em Saúde

Abstrato

A Case Study on Application of the Theory of Planned Behaviour:Predicting Physical Activity of Adolescents in Hong Kong

WK Mok* and Annie YK Lee

Objective: The aim of this case study was to predict the physical activity intention and behaviour of secondary school students in Hong Kong by applying the Ajzen’s Theory of Planned Behaviour (TPB) and past physical activity behaviour. Methods: 486 students (250 male and 236 female), ranging in age from 11 to 18 years, were enrolled in this study. By means of self-administrated questionnaire, demographic data, past physical activity and variables of theory of planned behaviour, such as attitude, subjective norm and perceived behavioural control were measured. Results: About 75% of students did not meet the standard of the physical activity recommended by government. Male had significantly higher behavioural intention than female. The variables of theory of planned behaviour explained 53.1% of physical activity intention with significant factors of subjective norm and perceived behavioural control (PBC), increasing to 56.2% with the addition of past physical activity behaviour. When predicting physical activity behaviour, theory of planned behaviour accounted for 26.6% of the variance. The prediction was further improved by including past physical activity behaviour. Conclusions: Results of this study give evidence that the theory of planned behaviour is a useful framework for prediction of physical activity intention of adolescents in Hong Kong. Among the variables, perceived behavioural control and past behaviour played a significant role in modelling the physical activity intention and behaviour of secondary students.