effect of educational intervention on knowledge, attitude and behavior about physical activity among grade 1 students of male high schools in bavanat, iran

background: regular physical activity has a positive effect on physical, mental, and social aspects of individual and community health. regarding prevalence of non-communicable diseases such as primary hypertension, osteoporosis, and cardiovascular diseases that sedentary is responsible for them, health policy makers plan to encourage people to do more physical activity. growth of beneficial health habits during childhood and the beginning stages of adolescence are very important because the behaviors of adolescence tend to continue at the adult period. this study aims to determine the effect of educational intervention on knowledge, attitudes and behaviors of the first grade students in male high schools of bavanat, iran about physical activity in the year 2010. methods: in this prospective experimental study, after selection of schools that have study conditions from five high schools, all students in a school (two classes including 42 individuals) randomly assigned to experimental group and all students of other high school (two classes including 43 individuals) randomly assigned to control group. data gathering tool was 4 parts - questionnaire includes demographic questions, information related to the knowledge and attitude questions related to physical activity. the first three parts of a questionnaire that was made by the researcher was validated by the face and content validity methods. test-retest and internal consistency (alpha cronbach) methods were used respectively to determine the reliability of knowledge questionnaire and attitude scale. for measurement of physical activity behavior in this study, self-reporting questionnaire (valid and reliable garcia scale) has been used. after pre-test, the educational intervention was done for the experimental group. post-tests were conducted immediately after training and one month after training. collecting data was analyzed using statistical software spss version18 (t-test, paired t-test, chi-square, mann-whitney test, and repeated measure anova). participation of students in this study was voluntary and conscious. findings: results indicated no significant difference between groups in mean scores of knowledge (p = 0.934), attitude (p = 0.155), and physical activity (p = 0.387) before the intervention. there was significant difference in mean score of knowledge in the immediate and follow-up (p < 0.001) and one month after intervention (p < 0.001) and also significant difference in mean score of attitude immediately (p < 0.001) and one month after intervention (p=0/01) in the experimental group compared with control group. mean score of physical activity one month after intervention in both experimental and control groups has significantly increased (p < 0.001, p = 0.01) but the mean score of physical activity between two groups has no meaningful (p = 0.390). conclusion: the results indicate the effectiveness of the educational intervention, resulting in greater awareness and attitudes of students in the experimental group compared with control group students in physical activity and thus increase their physical activity behavior. although the mean score of physical activity in control group was also significantly increased, other studies are recommended with regard to control confounder variables more.