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Background & objectives: A high percentage of musculoskeletal injuries are usually related to the lack of physical fitness. The most important performance of hand when doing work is grip strength and force in manual works. Work ability is a complex concept that can be assessed using the Work Ability Index (WAI) questionnaire. Because of the importance of making a balance between grip strength and work ability, the authors attempted to evaluate the relationship between grip strength and WAI.
Methods: This cross-sectional study was carried out among 120 kitchen workers. For the measurement of grip strength, pinch strength and WAI, by dynamometer, pinch gage and Iranian version of WAI have respectively been used. Data analysis was carried out by using SPSS 20. It is noteworthy to mention that p<0.05 was considered significant.
Results: in this study, maximum and minimum data for grip, pinch and WAI obtained 55 and 22 kg.f, 14 and 6 kgf, 49 and 27, respectively. Spearman's test showed no significant relationship between the WAI and pinch strength. However, the relationship between WAI and grip strength, was significant and direct (p<0.05).
Conclusion: In workplaces where grip strength is required, workers, weaknesses and their early withdrawal can be prevented by increasing WAI. It would consequently result in the reduction of the related diseases, lead to an increase in efficiency, and thus promote the health of the country's workers.

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Background & objectives: Occupational stress occurs when there is no coordination between the needs of the job with the individual abilities and desires. Physical ability of individuals is determined using the maximum aerobic capacity (VO2max), which is the maximum capacity to work during the shift.  The higher the aerobic capacity, the easier it is for a person to perform strenuous activities. The purpose of this study was to investigate occupational stress and its relationship with the maximum aerobic capacity and physical activity level in bank staff.
Methods: This cross-sectional study was performed among 82 bank staff that was selected by simple random sampling. To assess the Occupational stress, physical activity and VO2max, the Iranian version of HSE occupational stress and IPQA questionnaire and step test were respectively used. Data analysis was performed using SPSS-20 software. p≤0.005 was considered significant.
Results: In this study, bank employees were ranked in severe to moderate, well and moderate categories in terms of occupational stress, Vo2max and level of physical activity, respectively. There was also a significant relationship between occupational stress and age, weight, physical activity and VO2max (p≤0.05). But there was no significant relationship between occupational stress and height and BMI.
Conclusion: According to the results, the level of physical activity and especially Vo2max are considered as one of the factors affecting occupational stress. It seems that in order to reduce occupational stress and thus improve productivity, efforts to improve the level of physical activity and Vo2max are necessary.

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Background & objectives: Stress is a kind of physical or psychological exhaustion caused by real or imagined problems. Occupational stressors play a major role in influencing employees' actions by reducing focus and creating doubt. Three types of reaction time, including simple, diagnostic, and selective, are essential in the performance of various motor tasks.
Methods: This descriptive-analytic study was conducted cross-sectionally among 82 emergency personnel. Reaction time and job stress were measured using a reaction timer and the Iranian version of the HSE Job Stress Questionnaire, respectively. Data analysis was performed using SPSS-20, and a significance level of p<0.05 was considered.
Results: The mean values for job stress, simple reaction time, diagnostic reaction time, and selective reaction time in the study population were 125.51, 310.98, 473.50, and 453.82, respectively. An independent T-test indicated that gender does not affect occupational stress and reaction time. Additionally, according to the Pearson test, a significant inverse relationship was found between job stress and diagnostic and selective reaction times, indicating that as job stress increases (or stress reduces), a reduction in reaction time is observed (p<0.05). However, there was no significant relationship found between job stress and simple reaction time.
Conclusion: It is recommended that in jobs requiring high reaction time and accuracy, improving job performance by reducing individual stress should be prioritized. This approach can help prevent work-related accidents, which are sometimes caused by delayed responses. Additionally, it is advisable to monitor individuals not only through physical examination but also in terms of their mental and psychological conditions.