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Background: Endurance training can lead to tissue damage and destruction by creating oxidative stress. But, it seems that exhaustive and endurance swimming indicated different results with each other. The purpose of this research was to compare two kinds of endurance swimming training on levels of LDH, CK and MDA in male Wistar rats.

Materials and Methods: 18 male Wistar rats with 12 weeks old, weighting 250 to 300 g, were randomly divided into three groups (6 in each): 1) endurance swimming (EN), 2) exhaustive swimming (EX) and 3) Control (C). Both groups swam for 1 h/d and 5 d/w for 10 weeks. Swimming duration in EX groups was increased progressively by fiveth weeks, by 30 min/week, reaching 3 h/d by final 3 weeks of traninig protocol. In this duration, C group didn't receive any intervention. One day after the end of training protocol, blood samples of rats were obtained on vena cava. The activity of lactate dehydrogenase (LDH) and creatine kinase (CK) was measured with DGKC method and malondialdehyde (MDA) through reaction with TBA. Results were analyzed using the one- way ANOVA followed by a Tukey test. Significant level was 0.05.

Results: EN groups significantly increased the levels of CK compared with EX and C groups (p=0.001), when indicated significantly lesser levels of MDA than C group (p=0.011). But, no significantly difference observed in the levels of LDH.

Conclusion: It seems that endurance swimming creates more muscle damage, while were generates lesser lipid peroxidation.

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Background and Aim: Concerns are increasingly raised about the impact of social media use on depression in adolescents. This article aimed to summarize and synthesize quantitative studies addressing the association between social media and depression in adolescents.
Methods & Materials: This systematic review and meta-analysis included studies on the impact of the internet and social media use on depression in adolescents using Persian and English databases. In total, 15 studies met the inclusion criteria and were included in the analysis.
Ethical Considerations: All ethical principles are considered in this article. 
Results: The obtained data revealed a slight (0.18) statistically significant correlation (P<0.000) between social media use and depression in adolescents. However, this relationship was complex and associated with multiple psychosocial, behavioral, and individual factors, necessitating further investigation of mediating and moderating variables. Notably, most explored studies were cross-sectional; thus, they failed to infer the causal relationship between social media use and depression. In Iran, research has only investigated internet dependence. Further research is required in this area.
Conclusion: Overall, the mechanism of the impact of social media on depression should be further investigated through qualitative and longitudinal studies.

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