Historical perspective on physical employment standards

Development of an evidence-based swimming representative military task to assess swimming competency in the British Army

BACKGROUND

There is a requirement for British Army personnel to operate in/around water. Assessing role-related swimming/water competence will support personnel to conduct their job-roles safely and effectively.

OBJECTIVE

To undertake a Job-Task Analysis (JTA) of British Army personnel when working in/around water and use this information to develop a Swimming Representative Military Task (RMT) to assess swimming/water competence.

METHODS

Workshops, surveys, and observations were used to conduct a JTA, which identified and described job-tasks conducted by British Army personnel in/around water. Ergonomic analysis of these job-tasks identified seven water-based physical actions, which were considered fundamental for all personnel to be competent in performing. These seven actions guided design of a Swimming RMT, which was subsequently conducted twice by 103 serving personnel (89 men, 11 women) and once by 65 recruits (49 men, 16 women).

RESULTS

The RMT comprised of entering the water in combat fatigues and webbing, removing webbing, swimming 50 m, and staying afloat for up to 10 minutes. During RMT trials, in trial 1, 85% of serving personnel and 74% of recruits successfully completed the RMT, which increased to 93% in serving personnel for trial 2. Across trials 1 and 2, all three timed RMT elements showed moderate-high correlational reliability (ICC range: 0.462-0.791). On average, serving personnel were quicker to complete the 50 m swim phase compared to recruits (91±24 s vs. 100±26 s; U = 2575.0, rb = -0.192, p = 0.039).

CONCLUSIONS

The JTA-informed Swimming RMT provides an assessment of the minimum role-related swimming/water competence standard for British Army personnel.

A comparison of historical versus proposed physical employment standards for flight paramedics performing helicopter winch rescue

BACKGROUND

Paramedics working in helicopter teams undertake water and land rescues. Historical assessments of role-related fitness were not developed using physical employment standards methodology.

OBJECTIVE

To compare the historical selection tests with new tests developed via contemporary scientific methodology.

METHODS

Candidates undergoing selection to the role of flight paramedic (n = 14; age 37±5 yrs, body mass index [BMI] 26±4 kg.m2) undertook existing paramedic selection tests on land and in water, measurements of task duration, maximum heart rate (HRmax), rate of perceived exertion (RPE6 - 20) and capillary blood lactate (Lacmax) were recorded. These results were compared to the same variables in experienced paramedics (n = 14; age 44±5 yrs, BMI 25±3 kg.m2) who undertook the new tests.

RESULTS

Land task duration (existing 17±2 min vs. proposed 7±2 min, p <  0.05) HRmax (existing 186±13 b.min-1 vs. proposed 173±11 b.min-1, p <  0.05), and Lacmax (existing 23±3 mmol.L-1 vs. proposed 8±2 mmol.L-1, p <  0.05) were higher in the existing test compared to the proposed tests. Water task duration (existing 12±2 min vs. proposed 10±1 min, p <  0.05) was longer in the existing test, but HRmax (existing 166±18 b.min-1 vs. proposed 167±15 b.min-1, p = 0.90), Lacmax (existing 11±4 mmol.L-1 vs. proposed 11±4 mmol.L-1, p = 0.90) did not differ. RPE6 - 20 did not differ between groups for water or land.

CONCLUSIONS

The historical land-based physical tests for paramedics differed from the proposed tests, however the water-based tests had similar duration and physiological demands. Use of tests not developed via established scientific methodologies risks eliminating candidates suitable to work in the role, or including candidates that are not.

Physical demands at work and physical activity are associated with frailty in retirement

BACKGROUND: The relationship between occupational physical activity and frailty is complex and understudied. OBJECTIVE: We explore whether moderate-vigorous physical activity (MVPA) in retirement and main lifetime occupation physical demands (OPD) are associated with frailty in retirement. METHODS: Retired adults aged 50 + who participated in waves 3-4 of the Survey of Health, Ageing and Retirement in Europe were included. We constructed a 65-item frailty index (FI; Wave 4). Linear regressions tested the independent associations between OPD (Wave 3) and retirement MVPA (Wave 4) with FI (B: 95% CI) controlling for occupation characteristics (Wave 3) and demographics (Wave 4). These models were repeated across country groups (Nordic; Mediterranean; Continental) and sexes. RESULTS: We included 8,411 adults (51.1% male) aged 72.4 years (SD 8.0). Frequent MVPA was consistently associated with lower FI (-0.09 : 0.10–-0.08, p < .001) while OPD was associated with higher FI (0.02 : 0.01-0.03, p < .001). The MVPA*OPD interaction (-0.02: -0.04–-0.00, p = .043) was weakly associated with FI, but did not explain additional model variance or was significant among any country group or sex. CONCLUSIONS: For a sample of European community-dwelling retirees, a physically demanding main lifetime occupation independently predicts worse frailty, even in individuals who are physically active in retirement.

Exoskeleton Application to Military Manual Handling Tasks

OBJECTIVE

The aim of this review was to determine how exoskeletons could assist Australian Defence Force personnel with manual handling tasks.

BACKGROUND

Musculoskeletal injuries due to manual handling are physically damaging to personnel and financially costly to the Australian Defence Force. Exoskeletons may minimize injury risk by supporting, augmenting, and/or amplifying the user's physical abilities. Exoskeletons are therefore of interest in determining how they could support the unique needs of military manual handling personnel.

METHOD

Industrial and military exoskeleton studies from 1990 to 2019 were identified in the literature. This included 67 unique exoskeletons, for which Information about their current state of development was tabulated.

RESULTS

Exoskeleton support of manual handling tasks is largely through squat/deadlift (lower limb) systems (64%), with the proposed use case for these being load carrying (42%) and 78% of exoskeletons being active. Human-exoskeleton analysis was the most prevalent form of evaluation (68%) with reported reductions in back muscle activation of 15%-54%.

CONCLUSION

The high frequency of citations of exoskeletons targeting load carrying reflects the need for devices that can support manual handling workers. Exoskeleton evaluation procedures varied across studies making comparisons difficult. The unique considerations for military applications, such as heavy external loads and load asymmetry, suggest that a significant adaptation to current technology or customized military-specific devices would be required for the introduction of exoskeletons into a military setting.

APPLICATION

Exoskeletons in the literature and their potential to be adapted for application to military manual handling tasks are presented.

Development of physical employment standards of specialist paramedic roles in the National Ambulance Resilience Unit (Naru)

AIM

To develop evidence-based role-specific physical employment standards and tests for National Ambulance Resilience Unit (NARU) specialist paramedics.

METHODS

Sixty-two (53 men, 9 women) paramedics performed an array of (1) realistic reconstructions of critical job-tasks (criterion job performance); (2) simplified, easily-replicable simulations of those reconstructions and; (3) fitness tests that are portable and/or practicable to administer with limited resources or specialist equipment. Pearson's correlations and ordinary least products regression were used to assess relationships between tasks and tests. Performance on reconstructions, subject-matter expert and participant ratings were combined to derive minimum acceptable job performance levels, which were used to determine cut-scores on appropriate correlated simulations and tests.

RESULTS

The majority of performance times were highly correlated with their respective simulations (range of r: 0.73-0.90), with the exception of those replicating water rescue (r range: 0.28-0.47). Regression compatibility intervals provided three cut-scores for each job-task on an appropriate simulation and fitness test.

CONCLUSION

This study provides a varied and easily-implementable physical capability assessment for NARU personnel, empirically linked to job performance, with flexible options depending on organisational requirements.