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Introduction: In the field of sports, one of the theoretical approaches is the passion for physical activity, which is known to increase positive emotions in sports. The main purpose of this study was to determine the correlation of passion for physical activity and vitality with leisure time physical activity enjoyment in Tehran Municipality Sport Organization in 2019.
Methods: This study was a descriptive-correlational study. The statistical population included all employees of the Tehran Municipality Sports Organization, and the statistical sample was selected by the all-round method and 200 people due to the limited population. The study used "Passion Scale", "Subjective Vitality Scale", and the “Groningen Enjoyment Questionnaire". Formal validity, content validity index, convergent and construct validity and reliability (Cronbach's alpha coefficient calculation) were examined. Data were collected with a questionnaire. Data analysis used SmartPls 3.0 .
Results: There was a positive and negative significant correlation between harmonious passion                    (P = 0.001, β = -0.57), obsessive passion (P = 0.001, β = 0.57) with leisure time physical activity enjoyment. But there was not significant correlation between vitality (P = 0.338, β = -0.16) with leisure time physical activity enjoyment.
Conclusions: Compatible enthusiasm and extreme enthusiasm with the enjoyment of sports leisure time have a significant positive and negative correlation, respectively. Therefore, it is suggested that the managers of the Tehran Municipality Sports Organization, in order to create enthusiasm among the employees to participate in physical activity in their free time, undertake sports programs for some days of the week and in the form of family conferences.
 

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Introduction: All kinds of social networks have had profound and varied effects on the lives of people in human society, especially adolescents and young people. The aim of this study was to determine the correlation between self-efficacy and addiction to social networks with the motivation of academic achievement in high school students in Tehran.
Methods: The present study is descriptive-correlational. The statistical population included all high school students in Tehran in the academic year of 2009-2010. Using random cluster sampling, 422 people were selected and entered the study. To collect data from the demographic questionnaire, "General Self-Efficacy Scale", "Addiction to Mobile Questionnaire Based on Social Networks" and "Measurement Questionnaire" and the “Questionnaire Measure of Achievement Motivation” were used. Construct validity was measured by factor analysis method, convergent validity and reliability (Cronbach's alpha) of the instruments were measured. Data analysis was also performed by SPSS. 18 and PLS. 2.3.
 Results: The correlation between self-efficacy variables and motivation for direct and positive academic achievement and addiction to social networks was negative and direct, which is statistically significant (P≥0.05).
 Conclusion: There is a significant negative correlation between social media addiction and self-efficacy and between social media addiction and students' motivation for progress. It is suggested that education administrators and officials, through education, acquaint students with its harms and side effects and teach them ways to reduce and eliminate addiction to social networks. 

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Introduction: Exercise, as one of the most important leisure activities, has several educational purposes and can be effective in adapting criminals to the prison environment. The aim of this study was to compare the effect of exercise on violence of athletic and non-athletic criminals in Khuzestan province in 2017-2018
Methods: The present study was conducted in two stages: qualitative-quantitative (methodological) and descriptive-comparative. 
The statistical sample of the study in the qualitative stage of 12 people included employees, faculty members and criminals and in the quantitative stage of the research were 487 people (291 athletes and 196 non-athletes). Sampling in the qualitative stage was done by non-random and purposeful method and in the quantitative stage by systematic random sampling method based on Krejcie and Morgan Table. In the first stage (qualitative), the demographic questionnaire "Effect of Exercise on Criminals Violence Scale” was designed and the construct validity, divergent, convergent and combined reliability of the scale were measured. In the second stage (quantitative), the developed scale was distributed among the above samples. Data were analyzed by SPSS.22 and PLS. 23.
Results: In the qualitative stage, the "Effect of Exercise on Criminals Violence Scale" was developed with 36 items and 5 main themes of physical health, mental health, non-return to prison, reduction of violence and group participation. The results of the quantitative stage also indicate that the effect of exercise on reducing the violence of athlete criminals (0.57) compared to non-athlete criminals (0.41) was significant.
Conclusions: Considering the effect of sport in reducing the violence of criminals, it is suggested that managers and officials adopt more regular and extensive programs to establish sports classes and facilities in penitentiaries.