Journal of Health and Safety at Work

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Introduction. The effect of exercise program on the prevention of upper extremities musculoskeletal disorders has attracted the attention of researchers. On the other hand, in assembly workers, the risk of these disorders increases because the part of the body is used successively and without rest. The current study investigates the effect of 8 weeks of Kinesio Taping and sport program on grip endurance in female assembly workers of an electrical piece industrial manufacturer.
Materials and Methods. The current study was used a descriptive-analytic, cross-sectional method among 40 female assembly workers. Participants are exercised and used Kinesio taping for two times per week at eight weeks. The endurance of the grip was determined before and after the intervention by a dynamometer and the maximum time (in seconds) that one was able to continue one third of the maximum voluntary contraction. The DASH questionnaire was used to assess upper limb extremities’ disability. Data were analyzed using SPSS Ver.20 and the P value was considered smaller than 0.05.
Results. In the present study, the mean of right and left hand grip endurance in kinesio type and exercise group before intervention were obtained 10.55 and 9.51, whereas, related results after intervention were obtained 20.55 and 16.18, respectively. Also the score of upper limb disability in kinesio type and exercise group before intervention were obtained 10.55 and 9.51 and after intervention obtained 20.55 and 16.18, respectively(P <0.05).
Conclusion. According to the results, sport exercise and kinesio taping, lead to the increase in the grip endurance time and decrease in the upper limb disability.

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Introduction: Stressfull innate of the operating room, unpredictable types of activities, and prolonged standing during surgeries cause chronic fatigue in surgical technologists, resulting in reduced quality of care. It is essential, therefore, to provide especialized methods to reduce the surgical technologists’ fatigue severity.. This study was conducted to evaluate the effect of concomitant exercise and inhalation of lavender fragrance on surgical technologists’ fatigue severity.
Material and Methods: Ninety seven surgical technologists were recruited  in this clinical trial study, working in the operating rooms of Tabriz educational hospitals. They were randomly divided into three groups (Exercise, Lavender & Control) after fulfilling informed consent ,. The instruments for data collection included demographic information form as well as a multidimensional fatigue inventory questionnaire. In the experimental groups, concomitant exercise training and Lavender inhalation were both used for a period of six weeks while no intervention was given to participants in the control group. Statistical analyses were carried out using SPSS 20 as  well as  ANOVA and repeated measurement tests.
Results: No significant difference was observed between Exercise, Lavender, and Control groups regarding demographic characteristics (P>0.05). The mean score of fatigue between exercise and control groups and between Lavender and control groups showed a significant decrease (P<0.05). However, the results showed no significant difference statistically between the exercise and Lavender groups (P>0.05).
Conclusion: The concomitant exercise and Lavender fragrance in the operating room positively affect and reduce the fatigue severity in surgical technologists. Planning to implement similar interventions in the operating room is recommended.

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Introduction: Work-related musculoskeletal disorders (WMSDs) are one of the most important causes of absenteeism, increased costs and human injuries, which are very common in computer users. The purpose of this study was to investigate the effect of 8 weeks of corrective exercise on reducing the prevalence of musculoskeletal disorders (MSDs) in computer users working in a gas company.
Material and Methods: This cross-analytical study was conducted on 101 computer users working in a Gas Company in Qazvin city in 2019. Fourteen people participated in 8 weeks correction training intervention program (16 sessions in 1 hour and 2 times a week). Nordic questionnaire and body map were used in order to investigate the prevalence and severity of MSDs. The data were analyzed using Kolmogorov-Smirnov, Cramer V, McNamar, Paired sample t-test and Wilcoxon tests in SPSS version 23 software.
Results: The most common disorders were shoulder (64.3%), waist (42.9%) and neck (35.7%) regions among computer users during the last week before intervention. The prevalence of MSDsby strength and flexion exercises in neck and shoulder regions with 95% and 99% confidence showed a significant decrease before and after intervention. The incidence of discomfort in the waist region decreased by 35.8% after intervention and in other regions decreased by at least 7.1%.
Conclusion: The results of this study showed that implementation of corrective training intervention program by exercise specialists can increase muscle stretch and consequently decrease the prevalence of MSDs7.1%- 64.3%.

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Introduction: Prolonged sitting postures are among the risk factors for musculoskeletal disorders in occupational settings, leading to increased musculoskeletal discomfort in various body regions. This discomfort can negatively impact individuals’ health and impose high costs on society in terms of work absences, early disabilities, and reduced productivity. The purpose of this study is to investigate the effect of stretching exercises on the level of discomfort, muscle activity, and muscle fatigue in the neck and trunk region during prolonged sitting tasks.
Material and Methods: This experimental study was conducted among 20 healthy male and female participants under two test conditions: control and intervention. In the control condition, participants performed cognitive tasks (watching videos, typing, text editing, and nback cognitive test) without any intervention. In the intervention condition, participants performed stretching exercises before each task. The Visual Analogue Scale was used to assess perceived discomfort. Also, muscle fatigue was evaluated using an electromyography (EMG) device and RMS and MPF measures.
Results: Discomfort in hands and arms (p-value=0.04) and lower back (p-value=0.03) during video-watching was higher in the control condition than in the intervention. Regarding muscle activity, the activity of the right cervical erector spinae during the video-watching task was lower in the control condition than in the intervention. In the n-back cognitive test and text editing, the right lumbar erector spinae muscle activity was significantly higher in the control condition than in the stretching exercises intervention. Regarding the left cervical erector spinae, a significant difference was observed between fatigue in control and intervention conditions during the video-watching task. Also, right thoracic erector spinae fatigue in text editing was higher in the control condition than in the exercise intervention; however, for the n-back test, the level of fatigue was lower in the control condition compared to the intervention.
Conclusion: The perceived discomfort in seated computer tasks is generally lower in the exercise intervention compared to the control condition. The stretching exercises used in this study improved muscle activity and reduced fatigue in some of the trunk muscles, although the effects of the exercises depend on the type of task. Overall, muscle fatigue in two cognitive tasks, text editing and n-back, was more affected by stretching exercises than other tasks.

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Introduction: This study aimed to analyze the effects of endurance training (Aerobic) on the levels of inflammatory markers (IL-6/TNF-α) and some metabolic parameters in male rats with non-alcoholic fatty liver disease to investigate the feasibility of using exercise training to reduce inflammation.
Material and Methods: A total of 44 Wistar rats were randomly assigned into two groups: (I) standard diet group of 22 rats and (II) high-fat diet group with 22 rats supplemented with free access to fructose water. After 17 weeks, two rats from each group were sacrificed, and liver tissue was collected for hematoxylin-eosin staining. Subsequently, the remaining 20 rats in the (I) group were divided into a training group (T) and a control group (C). The 20 rats in the (II) group supplemented with fructose water were divided into a fatty liver group (FL) and a fatty liver + training group (FL+T), each comprising ten rats. In the next phase, the T-groups underwent an eight-week endurance training intervention. Then, IL-6, TNF-α, glucose, insulin, insulin resistance and sensitivity levels were measured.
Results: The results of the present study showed that as a result of a high-fat diet with liquid fructose in HFD+HF group rats, non-alcoholic fatty liver disease (NAFLD) with complications such as a significant increase in the levels of IL-6 and TNF-α, Hepatic dysfunction, and metabolic parameters were disturbed (p<0.001). However, endurance training improved most of these complications by reversing the disease process (p<0.001).
Conclusion: According to the results of the present study, it can be concluded that the improvement of inflammatory markers, liver dysfunction, and metabolic parameters through endurance training is one of the key mechanisms of exercise in the treatment of NAFLD, the consequences of which may show the importance of endurance training in treatment of NAFLD highlights.