Sam D. Blacker

Decades of research demonstrate that vigilance deteriorates rapidly and reliably and is often resistant to motivational override, yet ergonomic practice continues to assign monitoring tasks on assumptions the evidence does not consistently support. This paper argues that attentional capacity may be genuinely bound by biological architecture rather than merely variable in response to conditions. Drawing on empirical research and occupational vigilance data, we argue for what might be understood as a recovery of the foundational human factors philosophy of accommodation, calling for ergonomic design to redistribute cognitive work across human and machine capabilities in ways that respect the real limits of human attention.

Purpose Intake of anthocyanin-rich supplements such as New Zealand blackcurrant (NZBC) extract for 7 days showed beneficial effects on cardiovascular function at rest and during moderate and high-intensity exercise. The effects of 4- and 7-day intake of 600 mg of NZBC extract on cardiovascular function, femoral artery diameter, muscle force, muscle activity and muscle fatigue during low-intensity sustained intermittent isometric contractions were examined. Methods Fifteen healthy males (age: 25 ± 6 years, height: 180 ± 7 cm, body mass: 82 ± 8 kg) visited the laboratory on five occasions (familiarisation, days 4 and 7 of placebo (PLA) or NZBC extract intake). Each visit required the participants to hold the isometric contraction of the m.quadriceps femoris at 10% of their isometric maximal voluntary contraction (iMVC) for 5 bouts of 2-min. At the end of each 2-min, an iMVC was performed with subsequent 20 s rest before starting a subsequent bout. Electromyography, isometric muscle force, hemodynamic and ultrasound data were recorded. Results At days 4 and 7, there were no effects for NZBC extract on systolic blood pressure, diastolic blood pressure, heart rate, cardiac output, stroke volume, total peripheral resistance and femoral artery diameter. Although the isometric contraction protocol resulted in fatigue, there were no differences between PLA and NZBC extract conditions for isometric muscle force and muscle activity at days 4 and 7 (P > 0.05). Conclusion NZBC extract had no effect on cardiovascular function and exercise-induced fatigue during repeated bouts of low-intensity sustained intermittent isometric contractions of the m.quadriceps femoris, maybe due to the low demand of the exercise model.

Poor officer fitness can lead to decreased occupational task performance, injuries, increased absenteeism, and a variety of negative health sequalae further adding to the challenges of staffing law enforcement agencies. Optimizing the physical fitness for both serving officers and new recruits is critical as their loss is, and will increasingly be, difficult to replace. However, maintaining and recruiting a physically fit workforce faces several challenges. For serving officers, shiftwork is known to decrease motivation to exercise and negatively impact sleep and diet. Additional factors impacting their fitness includes age-related declines in fitness, increasing obesity, long periods of sedentarism, and negative COVID-19 effects. Concurrently, recruiting physically fit recruits is challenged by declining levels of fitness, reduced physical activity, and increasing obesity in community youth. Ability-based training (ABT), individualizing physical conditioning training based on the existing fitness levels of individuals within a group, offers a potential solution for delivering physical conditioning to groups of applicants, recruits, and officers with a range of physical fitness capabilities. Law enforcement agencies should consider implementing ABT during academy training and ongoing fitness maintenance to minimize injury risk and optimize task performance.

This study examined the impact of reduced sleep on electroencephalogram (EEG) activity during cognitive tasks in Military Clearance Diver trainees using a novel dry‐electrode EEG system. Seven male participants underwent two 5‐day periods: a baseline and a “live‐in” phase with increased workload and reduced sleep (5.4 ± 0.1 vs. 7.4 ± 0.7 h). EEG was recorded daily in the early morning (am) and late afternoon (pm) during a Psychomotor Vigilance Test (PVT), two oculography tests (am: n = 4; pm: n = 3), and 2 min of eyes‐closed rest. Significant increases in theta (t (29) = 2.308, p = 0.028, d = 0.421) and alpha (t (29) = 2.124, p = 0.042, d = 0.388) power spectrum densities were observed in the “live‐in” phase during the PVT. These findings align with increased lower frequency activity over time awake, reflecting heightened sleep propensity. Sleep loss was further confirmed by declining Odds Ratio Product (ORP) values. This study demonstrates the feasibility of dry‐electrode EEG in detecting fatigue‐related neural changes and highlights the potential of ORP as a quantifiable fatigue marker. These insights may inform operational settings, such as military diver performance monitoring and fatigue management strategies.

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.

Bouts of military load carriage are rarely completed in isolation; however, limited research has investigated the physiological responses to repeated load carriage tasks. Twelve civilian men (age, 28 ± 8 years; stature, 185.6 ± 5.8 cm; body mass 84.3 ± 11.1 kg and maximal oxygen uptake, 51.5 ± 6.4 mL·kg⁻¹ min⁻¹) attended the laboratory on two occasions to undertake a familiarisation and an experimental session. Following their familiarisation session, participants completed three bouts of a fast load carriage protocol (FLCP; ∼65 min), carrying 25 kg, interspersed with a 65‐min recovery period. Physiological strain (oxygen uptake [V̇O₂] and heart rate [HR]) was assessed during the FLCP bouts, and physical performance assessments (weighted counter‐movement jump [wCMJ], maximal isometric voluntary contraction of the quadriceps [MIVC] and seated medicine ball throw [SMBT]) was measured pre and post each FLCP bout. A main effect for bout and measurement time was evident for V̇O₂ and HR (both p < 0.001 and Ѡ² = 0.103–0.816). There was no likely change in SMBT distance (p = 0.201 and Ѡ² = 0.004), but MIVC peak force reduced by approximately 25% across measurement points (p < 0.001 and Ѡ² = 0.133). A mean percentage change of approximately −12% from initial values was also evident for peak wCMJ height (p = 0.001 and Ѡ² = 0.028). Collectively, these data demonstrate that repeated FLCP bouts result in an elevated physiological strain for each successive bout, along with a substantial reduction in lower body power (wCMJ and MIVC). Therefore, future research should investigate possible mitigation strategies to maintain role‐related capability.