Analysis of heart rate responses and physiological stress during law enforcement training

Heart rate and heart rate variability have been used to assess the physiological stress experienced by law enforcement officers during occupational tasks. Law enforcement officers who carry a firearm on duty must complete and pass a firearms training course and qualification with that weapon prior to carrying while on-duty. Previous research has shown that higher resting heart rates in law enforcement officers were associated with increased risk of violent altercations with suspects, which subsequently increased the likelihood of officer-involved shooting incidents. The purpose of this dissertation was to analyze the heart rate responses and physiological stress (via heart rate variability) of law enforcement officers during firearm qualifications and an active shooter training course. Major findings of this dissertation include: Heart rate variability was significantly reduced during firearm qualifications with both types of weapons, and throughout the duration of the active shooter training class. Significant differences were observed for average and maximum heart rate, and heart rate variability between the two types of firearms. Law enforcement officers in this dissertation achieved heart rates that equated to approximately 55-70% of maximal aerobic capacity during firearm qualifications, and up to 80% of maximal aerobic capacity during the active shooter training course, corresponding with moderate to vigorous work efforts. Heart rates during the active shooter training ranged from 71 to 108% of age-predicted maximum values, with group averages equating to approximately 86-93% of maximum heart rates. Comparatively, heart rates during firearm qualifications peaked at approximately 72 and 79% of age-predicted maximums for the pistol and rifle, respectively. Overall, this dissertation observed a difference in heart rate responses of law enforcement officers between pistol and rifle handling, and between qualification and situational/scenario trainings. Further research is needed to assess the influence of balance, stability, and recovery techniques like box or tactical breathing on marksmanship skills in law enforcement officers. Additional research is also recommended to assess the difference in physiological stress between training courses and on-duty events involving firearm discharge. Finally, incorporating additional subjective (i.e., questionnaires) and objective (i.e., salivary alpha-amylase or electroencephalography) measures of psychological stress would enhance law enforcement marksmanship training.