Effects of the transtheoretical model on physical activity, determinants, and perceived barriers of high school female students

The purpose of this study was to examine the transtheoretical model's intervention effects on physical activity, determinants and perceived barriers for high school female students. The study was also designed to investigate the effects of intervention on the processes of change and decisional balance for the high school girls.;Subjects involved in this study were three physical educators and their high school female students. Each participating teacher provided instruction for an experimental group and a control group of high school female students. A total of 74 high school female students (9th or 10 th grade) participated in this intervention study. The mean age of the subjects was 14.54 years (SD = .65). There were 36 high school female students in the experimental group and 38 high school female students in the control group. Students who consented to participate in the experimental group participated in five to seven-minute group discussions during classes and received handout information from the second week through the seventh week on the first day of each week. The control groups received no treatment between pre-tests and post-tests.;The independent variable was a six-week stage-based intervention program. The dependent variables were physical activity levels, stages of change, processes of change, decisional balance, determinants of physical activity, and perceived barriers of physical activity. The analysis of covariance (ANCOVA) or multivariate analysis of covariance (MANCOVA) was used to determine the effects of the intervention effects between the experimental and control groups. The pre-test scores were used as the covariates and the alpha level was set at p = .05. No significant difference was found between the control and experimental groups for the engagement in physical activity following the stage-based intervention. More subjects (above 40%) in both groups maintained their original stage (pre-action I or pre-action II) of exercise behavior following the intervention. In the experimental group, 12 (33.4%) subjects advanced one or more stages and 9 (25%) subjects relapsed one or more stages. In the control group, 9 (23.7%) subjects advanced one or more stages and 13 (34.2%) subjects relapsed one or more stages. Significant differences ( p < .05) were not found between the groups for stage of exercise behavior, determinants of physical activity, perceived barriers, decisional balance, and processes of change after the intervention.