Objectives: Law enforcement agencies require minimum fitness standards to safeguard their officers and training staff. Firearms instructors (FI) are expected to maintain the same standards as their operational counterparts. This study aimed to quantify the daily physiological demands placed on FI. Methods: 19 FI (45 ± 5 years) completed occupational tasks whilst wearing heart rate (HR) monitors for a minimum 10 days. VO2max testing was conducted on FI during a treadmill test (TT) and a multistage shuttle test (ST). Linear regression models were used to model the relationship between VO2 and HR throughout the TT. This model was applied to HR data from occupational tasks to infer oxygen consumption. Repeated Measures ANOVAs were used to compare time spent in VO2max equivalent zones throughout. Results: The VO2max achieved during ST (45.1 ± 5.6 ml/kg/min) was significantly higher than TT (39 ± 3 ml/kg/min) (p = 0.014). Time to exhaustion was sooner on ST (06:26 min) compared to TT (13:16 min) (p < .001). FI spent ~85% of occupational time with an oxygen demand ≤20 ml/kg/min (p < .005). The most intense occupational tasks saw FI achieve a VO2max ≥30 ml/kg/min, but <40 ml/kg/min. Conclusion: Using ST to assess cardiorespiratory fitness resulted in a quicker time to exhaustion and a higher VO2max. Predominantly, FI occupational tasks are low intensity with sporadic exposures requiring a VO2max of >40 ml/kg/min. To safeguard FI from occupational-related cardiorespiratory or long-term health issues, it is intuitive to suggest fitness standards should exceed a VO2max of 40 ml/kg/min.

The authors have declared no competing interest.

Yes this research was funded by the metropolitan police service.

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The study was approved by UCL's Ethics Committee (Project ID number: 13985/004) in line with the declaration of Helsinki.

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Data cannot be shared publicly because of confidentiality agreement with The Metropolitan police service. Data are available from the UCL Institutional Data Access / Ethics Committee, contact via corresponding author for researchers who meet the criteria for access to confidential data.