Background and Purpose
The authority, stability and security of a country are due to the round-the-clock efforts of its military forces and are closely related to the health, physical and combat readiness of those forces. For this reason, the main emphasis of commanders is to improve the physical and combat readiness of the forces, and for this purpose, they consider extensive and intense physical and sports training such as physical fitness training, combat and self-defense training, chase and escape, skill competitions, line-ups, long walks with backpacks, obstacle courses, artificial climbing, shooting and jumping from various heights during the training period. These exercises, like any other physical activity, are associated with the risk of musculoskeletal injuries. The results of various studies have shown that the most common type of injuries that occurred during military training courses were injuries resulting from physical and sports activities, and most of them were musculoskeletal injuries. Previous studies have also reported a high prevalence of musculoskeletal injuries in military training courses. Also, the occurrence of musculoskeletal injuries can have a significant impact on the level of combat readiness of the forces; in such a way that a fracture can disrupt an individual's activity for more than a hundred days and cause temporary or permanent disability, which in this case wastes millions of dollars of the operational budgets of military organizations annually. As a result, preventing injuries caused by physical and sports activities improves the health and performance of the individual, increases the duration of job activities, increases organizational productivity, and reduces the costs imposed on the organization due to absenteeism, treatment, and rehabilitation of the forces; therefore, the researcher decided to conduct an epidemiological study of musculoskeletal injuries caused by initial training exercises in the military forces and provide a comprehensive model for preventing these injuries.
Methods
The present study was of applied purpose and descriptive epidemiology prospective in terms of research method. The sample was approximately equal to the number of the statistical population of this study, which included non-commissioned officers of one of the military schools in the country, and 534 people were studied. The inclusion criteria for the study included an age range between 18 and 28 years, written consent for voluntary participation, no history of any chronic disease including cardiovascular and respiratory diseases, no physical disability and having a normal body mass index. The exclusion criteria included withdrawal of the subject from the training course, failure to cooperate with the researcher, and absence of more than 10 days during the training course. Physical fitness class exercises, self-defense exercises, arresting the accused, running and stopping consecutively, marching, standing still and so on were the main physical exercises and activities of the soldiers in this 10-month training course. In this study, a comprehensive questionnaire on musculoskeletal injuries, along with interviews, a review of medical history and records available in the school health center, such as radiographs, test results and diagnostic MRI by orthopedic, physical medicine, neurology, etc. specialists, and various forms were used to collect data and research information. The above was done monthly for 10 months. The comprehensive questionnaire on musculoskeletal injuries was used by Ristolinen et al and its validity and reliability were confirmed. In the final stage, the thematic analysis method was used to present the model. The steps of presenting the model in this study included collecting and categorizing data resulting from the opinions of experts, coding the data, identifying themes or common themes in the data, and finally interpreting and analyzing them and reporting in the form of a comprehensive injury prevention model in this study.
 
Results and Conclusion
In the present study, it was observed that 28.2% of the study samples suffered from various types of musculoskeletal injuries and the injury incidence rate was reported to be 1.15. Of all musculoskeletal injuries; 75.5% were acute injuries and 24.5% were chronic injuries. By examining other studies, we also see that the prevalence and incidence of musculoskeletal injuries among the military forces was high and in line with the results of the present study. In a study of the Dutch military forces, Dijksma et al (2020) observed that the prevalence of musculoskeletal injuries in these forces was between 26.8 and 60.4%, with an injury incidence rate of 12.5 to 53.3 per 100 people per year. In Yavnai et al’s (2021) study, it was also observed that 34.5% of the study samples suffered from musculoskeletal injuries after military training. Patrick et al (2019) also reported an injury incidence rate in the US Army of about 1.42 injuries per soldier. In Zarei’s study, about 40% of the study samples suffered injuries, with an injury incidence rate of 4.40 injuries per 1000 person-days. Zarei et al also reported in another study that the injury incidence rate in military training was high, with an incidence rate of 6 to 12 injuries per 100 soldiers per month and up to 30 injuries per 100 soldiers per month during training. Farahani et al also reported an injury prevalence rate of 27.3% and an incidence rate of 10.2 injuries per 100 soldiers per month in the Iranian military forces. According to the results of the present study, the highest prevalence of acute musculoskeletal injuries based on the injury site was reported as ankle/foot/toes (31.5%), knee (20.1%), and abdomen/pelvis/lower back/sacrum (15.7%), and the highest prevalence of chronic musculoskeletal injuries based on the injury site was reported as abdomen/pelvis/lower back/sacrum (45.9%) and knee (18.9%). The highest prevalence of musculoskeletal injuries based on the body region of injury was reported as lower limbs (54.4%) in acute injuries and trunk (45.9%) in chronic injuries. Although different studies have reported different rates of injury in different positions and areas of the military, researchers have noted a higher prevalence of injury in the lower limbs, especially the ankles and feet, as well as the back, than in other areas of the body. The results of these studies are consistent with the results of the present study, such that Dijksma et al (2020) reported that 23.2% of the reasons for Dutch military personnel visiting a doctor were due to musculoskeletal injuries of the back and lower back, knee and foot. Yavnay et al (2021) also reported the highest incidence of injury in the ankle, knee and calf, respectively and ankle sprain, knee and calf pain were the most common types of injury. According to Patrick et al (2019) musculoskeletal injuries of the lower limbs and back were the most common injuries reported among US military personnel during military training. The most common sites of musculoskeletal injuries were reported to be the knee (19%), ankle (16%) and shin (8%). According to the study by Seydi et al the highest incidence of injuries was observed in the ankle, knee and back of soldiers. Ghaderi et al also observed the highest incidence of injuries in the lower limbs of soldiers in their review study, or Nodehi Moghadam et al. reported the most common injury sites as knee (45.4%), back (30.0%) and ankle (17%). In Zarei's study, knee (48%), ankle (30%), and shin (19%) were the most common injury sites, and Farahani et al also reported the knee as the most vulnerable site of the body of Iranian soldiers during the training period with more than 27%. In the observed results of the present study regarding the severity of injuries, 956 days were reported lost due to all musculoskeletal injuries. Also, 75.4% of the observed injuries were mild, 10.5% were moderate and 14.1% were severe. Havantidis et al (2011) also reported the severity of 82% of the injuries of Greek soldiers during the training period as mild or mild. In 10% of the injuries, the severity of the injury was so severe that the soldier had to leave the training period. In the study by Zarei et al about 69% of the injuries of these soldiers were mild, 20% were moderate and 8% were severe.
Now, using the results of the thematic analysis of the data of this study and the opinions of experts, we will present a model for preventing injuries in these individuals:
1. Changing the parade model
2. Using appropriate boots
3. Using shock-absorbing insoles in boots
4. Preventing overtraining in physical activities and sports training
5. Preventing overtraining in parades and formations
6. Teaching proper warm-up and cool-down
7. Performing injury prevention training protocols and corrective exercises protocols
8. Appropriate scheduling of physical activities and sports training
9. Teaching the principles of exercise science and injury prevention
10. Specialized entry assessment (posture and functional screening to predict injury)
11. Using injury prevention equipment 
Article Message
According to the results of the present study, it was observed that the prevalence of musculoskeletal injuries among military forces was high. By examining the cause and mechanism of injuries, the possible risk factors for injury in these forces were identified, and based on this, a comprehensive injury prevention model in military forces was proposed.
 
Ethical Considerations
In conducting the research, ethical considerations were taken into account in accordance with the guidelines of the Ethics Committee of the National Institute of Physical Education and Sport Sciences, and before conducting the research, the ethics code number IR.SSRI.REC.1400.1350 was received from the aforementioned research institute. In conducting this research, paying attention to ethical considerations was of particular importance and efforts were made to respect the privacy of all subjects, to use their information anonymously and confidentially, and solely for research, and to provide them with the results of this research if they needed training or guidance. Subjects were allowed to have full authority to cancel their participation at any stage of the research. Also, great care was taken in transparency and honesty in data collection and their accuracy.
Authors’ Contributions
In this study, the first author, as the corresponding author, was responsible for idea generation and Conceptualization, literature review, data collection and analysis and Manuscript writing in collaboration with the second author. The second author was responsible for reviewing and editing, project management and the guidance and supervision of all research activities.
Conflict of Interest
According to the authors, this article has no conflict of interest.
 
Acknowledgments
This research is the result of a research project introduced by the Armed Forces Elite Foundation in one of the country's military organizations. We would like to thank and appreciate all the people who helped us in conducting this research.