The effect of physical fitness level on mir-155 gene expression mediated by job stress in Shiraz firefighters

Subject Areas : Journal of Physical Activity and Hormones

Kamran Rajabi ¹ , Homa Sheikhani Shahin ²

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Received: 2025-04-30 Accepted : 2025-06-30 Published : 2025-07-15

Keywords: Physical fitness, Job stress, mir-155, Firefighters,

Abstract :

Introduction: Firefighters are increasingly exposed to factors that affect their physical and mental health. The aim of present study was examined the effect of physical fitness level on mir-155 gene expression mediated by job stress in Shiraz firefighters.

Material & Methods: Twenty firefighters volunteered to participate in this study. To measure the physical fitness of the subjects, the Physical Fitness Index Questionnaire (Sharkey, 1990) was used, and to assess the level of job stress, the Job Stress Questionnaire (Elliott, 1994) was used. The expression of the mir-155 gene was also measured by Real-time PCR. Smart PLS software was used to analyze the data, with a significance level of p<0.05.

Results: The results showed that the level of physical fitness and job stress did not have a direct and significant effect on the expression of the mir-155 gene in Shiraz firefighters, and the level of physical fitness also did not have a direct and significant effect on their job stress.

Conclusion: These results indicate that to improve the health and performance of firefighters, attention should be paid to other factors that may have a greater impact on gene expression and job stress.

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