Infantry Personnel Research Articles

Musculoskeletal Injury in Australian Infantry Personnel: A Cross-sectional Study to Understand Prevention Priorities.

Musculoskeletal injury patterns are under-investigated in the Royal Australian Infantry Corps. Subsequently, more evidence is needed to support injury prevention processes in this population. One difficulty in collecting injury information to monitor injury patterns within combat populations accurately is known injury concealment behaviors in such populations. This study aims to examine musculoskeletal injury epidemiology within Australian infantry battalions using a tailored approach to mitigate reporting avoidance. A cross-sectional study using an anonymous online survey captured musculoskeletal injury information directly from personnel serving within 2 Australian infantry battalions. The survey requested information on participants' injury frequency in the previous 12 months and the context of participants' most severe injury. Injury context was restricted to the most severe during the period to limit recall bias. The applied injury case definition encompassed all injuries that affected an individual's ability to perform in their role. A descriptive analysis of all data recorded across the 2 battalions was conducted. Subgroup statistical difference was assessed by examining the 95% CI overlap between groups. The Department of Defence and Veterans' Affairs Human Research Ethics Committee granted ethical approval for this study. Overall, 166 individuals self-reported at least 1 injury in the past 12 months, representing a period prevalence of 55.5% (95% CI, 49.8-61.0%). No statistically significant prevalence differences existed between employment type, age, or sex. Approximately a quarter of injured participants were medically reclassified because of their injury, impacting their deployment fitness (n = 40, 24.4%). The following results relate to the most severe injury personnel experienced. Most injuries were service-related (n = 152, 91.6%). Field activities (n = 64, 39.3%) and physical training (n = 59, 36.2%) were the most common injury-related activities. Running was the most reported injury mechanism (n = 35, 21.7%), followed by pack marching (n = 29, 18.9%) and fall, slip, or trip (n = 18, 11.2%). Musculoskeletal injuries are common in the Australian infantry and significantly burden the workforce. Physical training and field exercises are most associated with injury and represent opportunities for injury risk-mitigation strategies to support the overall deployability of personnel and the combat effectiveness of their battalions. Future research should more formally explore the injury risk factors related to these activities using more robust study designs to collect injury and exposure information more accurately and reliably. One study strength includes using military-specific international injury surveillance guidelines to inform the survey design, to collect the recommended injury information for effective surveillance, and to enable future research comparison. A second study strength was tailoring the survey to promote participatory engagement, providing a high completion rate. A challenge in conducting this research was coordinating participant recruitment and data collection during domestic operations. Such challenges reflect the reality of conducting research in the military.

Don't Shoot Me: Potential Consequences of Force-on-Force Training Modulate the Human Stress Response.

Jensen, AE, Bernards, JR, Hamilton, JA, Markwald, RR, Kelly, KR, and Biggs, AT. Do not shoot me: potential consequences of force-on-force training modulate the human stress response. J Strength Cond Res 37(9): 1761-1769, 2023-Close-quarters combat (CQC) engagements trigger the "fight-or-flight" response, activating the sympathetic nervous system and hypothalamic-pituitary-adrenal axis in response to perceived threats. However, it has yet to be shown if a force-on-force (FoF) CQC training environment will lead to adaptations in the physiological stress response or performance. United States Marines and Army infantry personnel participated in a 15-day CQC training program. The CQC program focused heavily on FoF training with the use of nonlethal training ammunition (NLTA). Data collections occurred on training days 1 and 15, during a simulated FoF-hostage rescue (HR) scenario and photorealistic target drill. For the FoF-HR, subjects were instructed to clear the shoot house, rescue the hostage, and only shoot hostile threat(s) with NLTA. The photorealistic target drills were similar, but replaced the role players in the FoF-HR with paper targets. Salivary alpha-amylase (sAA) and salivary cortisol were obtained immediately before entering and exiting the shoot house. Time to completion significantly decreased, between days 1 and 15, for both the FoF-HR and the photorealistic drills by 67.7 and 54.4%, respectively ( p < 0.05). Analyses revealed that the change in sAA, nonsignificantly, doubled from day 1 to 15 during FoF-HR ( p > 0.05), whereas the change in sAA decreased during the photorealistic drills across days ( p < 0.05). Cortisol was significantly higher during the FoF-HR in comparison to the photorealistic drills ( p < 0.05). These data suggest that potential consequences of FoF training heighten the stress response in conjunction with enhanced performance.

The impact of the mechanical whole-body vibration experienced during military land transit on the physical attributes underpinning dismounted combatant physical performance: A randomised controlled trial

ObjectivesThe aim of this randomised controlled trial was to explore the impact of the mechanical WBV experienced during simulated military land transit on the physical attributes that underpin tasks performed by dismounted combatants. DesignThis study used a parallel group randomised control trial design. MethodsSixty participants were randomly assigned to one of four, 2-h laboratory-based simulations (restricted posture, sealed road, cross country or a control condition). A smaller sample of 16 Australian Defence Force infantry personnel served as a validation group and were exposed to the same conditions. Neither the restricted posture nor the control conditions were exposed to any WBV, but the former were secured in place using the built-in seat harness. Prior to, and following the assigned condition, participants performed a series of battlefield relevant physical performance tests including; drop jump, 20-m sprint, reactive agility, arm-hand steadiness, isometric mid-thigh pull, and sit-and-reach. ResultsMedium decreases in the drop jump were observed for both the sealed road (effect size [ES]=0.53) and cross-country (ES=0.97) simulation conditions indicating a decrease in performance of the jump phase. A large decrease in 20-m sprint performance was observed in both the sealed road (ES=1.37) and cross-country (ES=0.88) exposure conditions. Additionally, a large decrease in 20-m sprint performance was observed for the restricted posture (ES=1.02) exposure condition. ConclusionsThese findings indicate that exposure to WBV experienced during motorised land transit has a negative influence on aspects of lower body explosive strength.

Emergency Operation and Coordination Center (EOCC) for Disaster Response Management

Disaster management is often portrayed in negative rather than positive terms. Although, it is claimed that proper preparation for any disaster has been planned, it frequently fails to achieve positive outcomes from the planning itself. The emergency operation and coordination center (EOCC) which is the central point for all coordination and organising works is normally to be blamed for disaster response failure. Hence, the objective of this study is to examine issues with effective emergency operation and coordination center (EOCC) during disaster response. This study uses a qualitative research method. The researcher conducts an interview survey and focus group discussion for data collection in order to gain a comprehensive overview of the situation and understand the phenomena involved. The population for this study is infantry army officers. Purposive sampling is used such that only those personnel involved in disaster response are interviewed. This study found that the EOCC organization structure is clear and it follows the command and control military hierarchy. The leader with the relevant rank, having the experience and knowledge on managing disaster and having the respect and control from subordinates is appointed for the leadership role in the EOCC. However, inter-agency cooperation can be an issue as there is an overlapping of roles and responsibilities and inter-agency power struggle. Therefore, this issue leads to chaos and tension in the EOCC as there would be variance and inconsistency in the coordination and communication among infantry personnel and inter-agency.

The shared motorised military land transit experiences of Australian Defence Force infantry personnel

Introduction: The increased use of mechanised fighting forces means that the modern infantry unit is exposed to a range of stressors on a more frequent basis. In order to understand how these stressors may impact infantry personnel, it is important that the ‘typical’ motorised land transit experiences be identified. The purpose of this study was to identify the shared motorised military land transit experiences of Australian Defence Force (ADF) personnel.

The application of a mathematical model to estimate the aerobic capacity required to complete an 8-mile loaded march from an individual's body mass

Introduction: The British Army Annual Fitness Test (AFT) for Infantry personnel is an 8-mile Loaded March (LM) that must be completed in 2 h, carrying 25 kg. The study aims were (1) to develop a mathematical model to estimate the minimum V ˙ O 2 max and 2.4 km run time (RUN) to successfully complete the AFT and (2) quantify the proportion of a sample of British Army recruits who could meet the pass standard.

Pirate Stealth or Inattentional Blindness? The Effects of Target Relevance and Sustained Attention on Security Monitoring for Experienced and Naïve Operators

Closed Circuit Television (CCTV) operators are responsible for maintaining security in various applied settings. However, research has largely ignored human factors that may contribute to CCTV operator error. One important source of error is inattentional blindness – the failure to detect unexpected but clearly visible stimuli when attending to a scene. We compared inattentional blindness rates for experienced (84 infantry personnel) and naïve (87 civilians) operators in a CCTV monitoring task. The task-relevance of the unexpected stimulus and the length of the monitoring period were manipulated between participants. Inattentional blindness rates were measured using typical post-event questionnaires, and participants' real-time descriptions of the monitored event. Based on the post-event measure, 66% of the participants failed to detect salient, ongoing stimuli appearing in the spatial field of their attentional focus. The unexpected task-irrelevant stimulus was significantly more likely to go undetected (79%) than the unexpected task-relevant stimulus (55%). Prior task experience did not inoculate operators against inattentional blindness effects. Participants' real-time descriptions revealed similar patterns, ruling out inattentional amnesia accounts.

Fit for the frontline? A focus group exploration of auditory tasks carried out by infantry and combat support personnel.

In order to preserve their operational effectiveness and ultimately their survival, military personnel must be able to detect important acoustic signals and maintain situational awareness. The possession of sufficient hearing ability to perform job-specific auditory tasks is defined as auditory fitness for duty (AFFD). Pure tone audiometry (PTA) is used to assess AFFD in the UK military; however, it is unclear whether PTA is able to accurately predict performance on job-specific auditory tasks. The aim of the current study was to gather information about auditory tasks carried out by infantry personnel on the frontline and the environment these tasks are performed in. The study consisted of 16 focus group interviews with an average of five participants per group. Eighty British army personnel were recruited from five infantry regiments. The focus group guideline included seven open-ended questions designed to elicit information about the auditory tasks performed on operational duty. Content analysis of the data resulted in two main themes: (1) the auditory tasks personnel are expected to perform and (2) situations where personnel felt their hearing ability was reduced. Auditory tasks were divided into subthemes of sound detection, speech communication and sound localization. Reasons for reduced performance included background noise, hearing protection and attention difficulties. The current study provided an important and novel insight to the complex auditory environment experienced by British infantry personnel and identified 17 auditory tasks carried out by personnel on operational duties. These auditory tasks will be used to inform the development of a functional AFFD test for infantry personnel.

Mental health among commando, airborne and other UK infantry personnel

Despite having high levels of combat exposure, commando and airborne forces may be at less risk of mental ill-health than other troops. To examine differences in mental health outcomes and occupational risk factors between Royal Marines Commandos (RMCs), paratroopers (PARAs) and other army infantry (INF). Three groups of personnel (275 RMCs, 202 PARAs and 572 INF) were generated from a UK military cohort study of personnel serving at the time of the 2003 Iraq war. Participants completed a questionnaire about their mental health and experiences on deployment. Differences in mental health outcomes between the groups were examined with logistic regression and negative binomial regression analyses. Both RMCs and PARAs were less likely to have multiple physical symptoms or to be fatigued, and RMCs also had lower levels of general mental health problems and lower scores on the Post-traumatic Checklist than INF personnel. Differences were not explained by the level of unit cohesion. The effect of warfare on troops' well-being is not universal across occupational groups. A possible explanation for this difference is that the high level of preparedness in RMCs and PARAs may lessen the psychological impact of war-zone deployment experiences.

The Effect of Auditory Display Configuration and Physical Load on Message Intelligibility for the Dismounted Soldier

The purpose of this study was to determine the extent to which different types of audio display technology affected the ability of the physically active, load-carrying dismounted soldier to understand and respond to multiple radio communications in the battlefield. Independent variables were different types of auditory display configuration (existing monaural and spatial audio), number of simultaneous talkers in each simulated radio message (two, three, or four), and soldier rucksack load (22 kg or 33 kg). The dependent variables included the response time and number of accurate responses to the radio messages, soldier ratings of mental workload, and soldier physiological workload. Subjects were nine (9) male Marine Corps Infantry personnel and three (3) male Army Infantry personnel. Results indicated that spatial auditory displays enabled soldiers to identify a significantly greater number of simulated radio communications, and respond to these communications more quickly. Message response time increased and identification accuracy decreased as the number of simultaneous talkers increased. Rucksack weight was a predominant variable in physical and mental workload. Soldiers showed significantly greater physiological energy expenditure and significantly greater mental workload when they carried the heavier rucksack. The results indicated that whatever the load carried by the soldier, the speed and accuracy of understanding and responding to multiple radio communications were enhanced by presentation in different spatial locations.

Evaluating the Occupational Physical Fitness of Canadian Forces Infantry Personnel

Fitness in the military is a time-honored and unquestionable axiom. Yet, there is limited objective knowledge as to what criteria of fitness are necessary to maintain combat effectiveness during sustained operations and how they should be assessed. The purpose of this study was to design an indoor standardized obstacle course (ISOC) related to specific trade-related tasks. A 19-item indoor obstacle course consisting of running, crawling, scaling, pulling, lifting, carrying, and pushing events arranged in a sequential order was designed. Forty-three healthy male subjects between the ages of 21 and 31 years underwent a series of intensive laboratory testing. They then ran through the obstacle course, set up in a local armory, on three separate occasions. Results indicated that ISOC performance is related to fitness components identified as important in the performance of military tasks, namely, aerobic and anaerobic power, muscular strength and endurance, and body composition. The ISOC provides a practical and challenging procedure to assess the fitness readiness of infantry and other field units in the Canadian Forces.