The Journal of

Introduction: Unhealthy life style causes health risks as well as non-communicative diseases in the adulthood. Theory- based educational needs assessment before-intervention can be introduced as a basis among adolescents regarding education planning in lifestyle promotion. Therefore, this study aimed to examine the influential factors in adopting lifestyle-promoting behaviors in adolescents using theory of planned behavior.

Methods: In this cross-sectional analytic study, a sample of 175 students, aged 12-15 years, were selected via multistage random sampling. In order to glean the study data, a questionnaire was utilized based on constructs of planned behavior theory with regard to adolescent's life style. The study data were analyzed using SPSS software (ver. 20) via Pearson correlation, independent t-test and multi factorial regression.

Results: The students' mean age was reported 13.5, 0.9 years. Quality of life decreased with increasing age of the students and their fathers' education level. No association was found between intention and behavior in healthy eating (P= 0.438) as well as smoking and alcohol rejection (p= 0.256). Healthy eating behavior (B=0.638) and intention (B=0.268) were most predicted by attitude. Intention in physical activity was most predicted by perceived behavioral control (B=0.244) and behavior (B=0.424) was most predicted by the subjective norms. Regarding stress management, intention was most predicted by subjective norms (B=0.455) and behavior was most predicted by the perceived behavioral control (B=0.767). In smoking and alcohol rejection, attitude (B=0.829) showed a strong association with intention and perceived behavioral control (B=0.311) revealed a strong relationship in regard with behavior. 

Conclustion: Lack of association between intention and behavior demonstrated that demographic variables, except for intention, may affect behavior in adolescents. Educational interventions focusing on perceived behavioral control construct seem to be an important way to achieve the healthy behavior. Since physical activity behavior was directly affected by the subjective norms, promoting exercise behaviors in the age groups will be more successful with the family cooperation.