Background
Body image is a determinant of individual attractiveness and physical activity among the young people. This study was aimed to assess the association of Trans-theoretical model based exercise behavior change with body image evaluation among the female Iranian students.
Materials and Methods
This cross-sectional study was conducted in Sanandaj city, Iran in 2016. Using multistage sampling method, a total of 816 high school female students were included in the study. They completed a three-section questionnaire, including demographic information, Trans-theoretical model constructs and body image evaluation. The obtained data were fed into SPSS version 21.0.  
Results
The results showed more than 60% of participants were in the pre-contemplation and contemplation stages of exercise behavior. The means of perceived self-efficacy, barriers and benefits were found to have a statistically significant difference during the stages of exercise behavior change (P<0.05). Moreover, there was a significant correlation between the stages of exercise behavior change and fitness evaluation, fitness orientation, subjective weight and body areas satisfaction subscales (P<0.05). The interaction effect of self-efficacy and body image on exercise behavior were reported to be statistically significant (P<0.05).
Conclusion
The findings of this study indicated poor physical activity and effect of body image on doing exercise. Body image and designing interventions to promote exercise behavior are suggested to be taken into account.