Elham Molavi Vardanjani - MSc in Health Education. Department of Health Education and Health Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Ahmadali Eslami - Professor of Head of Department of Health Education and Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Ashraf Aminorroaya - Professor of Internal Medicine and Endocrinology, Isfahan University of Medical Sciences, Isfahan, Iran
Akbar Hassanzadeh - Department of Biostatistics, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. ۵Associate Professor, Head of Department of Health Education and Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Zohre Fathian Dastgerdi - Assistant professor in Health Education and Promotion. Department of Health Education and Promotion, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran

Background: The prevalence of type ۱ diabetes mellitus (T۱DM) is a universal problem for many countries. Regular physical activity (PA) has a key role in the management of T۱DM. This study aimed to determine the influence of a social cognitive theory (SCT)-based educational intervention on promoting PA among adolescents with type ۱ diabetes.Methods: The present is an intervention study (IRCT۲۰۱۹۰۱۱۳۰۴۲۳۴۱N۱). A total number of ۸۰ patients were recruited in study and then randomly assigned to two groups of intervention (n = ۴۰ individuals) and control (n = ۴۰ individuals). After that, a researcher-made multipart. The questionnaire included demographic information form, self-care behaviors, self-efficacy, outcome expectations, self-regulation and social support. The intervention group received selfcare educational intervention based on the SCT constructs in six sessions, and then they were supervised and followed by their friends in the social network as a peer group. The adolescents completed the questionnaire in three steps (before, immediately, and six mounts later). The data were analyzed through Repeated Measures ANOVA, ANCOVA, and regression analysis by SPSS.۲۳ software.Results: The mean age of participants was ۱۶.۷±۲.۷ years. There was a significant improvement across time in the mean of PA (P<۰.۰۰۱) and SCT constructs mean (P<۰.۰۵) inthe intervention group. The results of hierarchal regression showed that the SCT constructs could significantly explain the PA behavior in adolescents (AdjR۲=۰.۴۱, P<۰.۰۰۱), and selfefficacy is the strongest explanator for PA behavior in adolescents with type ۱ diabetes.Conclusion: According to the findings of this study, the use of self-efficacy improvement methods and strategies in diabetic youth can be effective in promoting their self-care. In addition, The results of this research can be used as a basis for future researches like the design and evaluation of educational supportive.

Physical Activity, Adolescents, Social Cognitive Theories, Type ۱ Diabetes