Masoumeh Motamedi - Department of Health Education & Health Promotion, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran
Nooshin Peyman - Department of Health Education & Health Promotion, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran
Monavar Afzalaghaee - Department of Statistics and Epidemiology, School of Public Health. Mashhad University of Medical Sciences, Mashhad, Iran.

Background and Objective: Health literacy exerts a positive effect on the improvement of self-management behaviors. Along with lifestyle, it is among the social factors affecting health. Self-efficacy is a predictor of health behaviors, including physical activity. With this background in mind, the present study aimed to determine the relationship between health literacy and regular physical activity self-efficacy with body mass index in adolescent girls aged 15-18 years.   Materials and Methods: This descriptive-analytical study was conducted based on a cross-sectional design in 2016-2017 academic year. In this study, 439 students were selected from Chenaran using multistage cluster sampling. Data were collected using demographic information questionnaire, health literacy questionnaire, and regular physical activity self-efficacy questionnaire and analyzed in SPSS software (version 16) using appropriate statistical tests. Results: The mean age of participants was reported as 16.51±1.03 years (age range: 15-18). The mean body mass index was 21.3± 3.64, and the mean score of health literacy was obtained at 0.78±0.93. The results also revealed that there was a significant difference between the mean scores of students' health literacy in the four levels of body mass index (p <0.0001). The self-efficacy of regular physical activity in obese and overweight students was lower, compared to that reported in students with normal BMI. Conclusion: In general, health literacy, physical activity self-efficacy, and body mass index in students were not optimal. This finding highlights the need for health education intervention programs based on the components of health literacy and self-efficacy.

Health Literacy, Adolescents, Self-Efficacy of regulate exercise, Body mass index