Modifying the theory of planned behavior to predict exercise behaviors among children

• Main Author: Wigginton, Melissa L
• Format: Dissertation
• Language: English
• Subjects: education, health; education, physical; health sciences, public health
• ISBN: 9781124806303; 112480630X

Background. In the Theory of Planned Behavior (TPB), intention and perceived behavioral control are the proximate predictors of behavior (Ajzen, 1991). However, when the TPB is used with children, behavior is not predicted well from intention (the so-called intention-behavior gap).
Purpose. To answer the following: (a) Do attitude, subjective norm, and perceived behavioral control directly predict children's exercise behaviors better than intention? (b) Can other factors---e.g. BMI, SES, age, past exercise behaviors and strategic planning--- improve prediction of the child's behavior? (c) Does the strength of the relationship between intention and behavior increase as the child's age increases?
Method. Children ages 9 to 14 years, from two charter schools in San Bernardino County were given a 35-item TPB questionnaire and the physical activity questionnaire for older children (PAQ-C). One week later children were given the PAQ-C and had their height and weight measured. Parental consent and participant assent were obtained prior to data collection.
Results. Instrumental and experiential attitude, injunctive and descriptive subjective norm and PBC-controllability and PBC-Capability were found to be significant, direct predictors of children's exercise behaviors explaining 25.9% (p < .001) of the variance in exercise. The modified TPB (leaving out intention) was found to be a significantly better fit to the data [Z (345) = 3.11, p = .002] than the original model---predicting 9.7% more of the variance in children's exercise behaviors. Intention was not a significant predictor of exercise once the other TPB variables were included. Injunctive descriptive norms, gender and age were found to be significant independent predictors of exercise, while experiential attitude approached significance ( p = .053). The intention-behavior relationship was not found to improve with the child's age. Planning was found to predict attitude, subjective norm, and perceived behavioral control. Also, the variables that predicted leisure exercise were different from those that predicted in-school exercise.
Conclusions. The results of this study will help improve prediction of exercise behaviors among children. Several findings regarding the various influences of children's exercise behaviors can be used by program planners and implementers to predict children's exercise behaviors and develop successful, more appropriate exercise-based interventions.