the survey of theory of planned behavior constructs regarding girl student’s physical activity in naein payame noor university in 2012

background: reduction of physical activity among people is one of the most important problems of society which is resulted from life industrialization. the aim of this study was to survey knowledge and theory of planned behavior constructs inclusive attitude, intention, subjective norms and perceived behavioral control regarding girl student’s physical activity in naein payam noor university in 2012. methods: in this cross-sectional study, 130 girl students were selected by simple random sampling. data gathered with a questionnaire with acceptable validity and reliability consisting of demographic data, knowledge and constructs of theory of planned behavior. data analysis was performed with spss-18 software and related statistical tests.  findings: 130 females with mean age of 22±2/8 years were participated in this study. the mean scores of knowledge, attitude, intention, subjective norms and perceived behavioral control were: 74±14/6, 81/1±14/2, 52/3±25/3, 60/3±23/9 and 48/1±13/3 respectively. there were significant differences between physical activity performance intention with knowledge (p=0/011), attitude (p=0/000), subjective norms (p= 0/000) and perceived behavioral control (p=0/019). conclusion: according to this study, physical activity intention had significant correlation with attitude and subjective norms. thus, with apply educational sessions based on attitude change for example: group discussion and also the same sessions for important others such as: family, friends, classmate and so on we will be able to promote physical activity in girl students.