Gregory S. Anderson

Physical evidence of police officer stress

The purpose of the present study was to identify common stressors and the magnitude of stress reactivity in police officers during the course of general duty police work. Using heart rate as a primary indicator of autonomic nervous system activation, coupled with observed physical activity data collected through 76 full shift ride‐alongs, this study differentiates between physical and psycho‐social stress. The results, confirming previous research based on self‐report data alone, demonstrate that police officers experience both physical and psycho‐social stress on the job, anticipating stress as they go about their work, while suffering anticipatory stress at the start of each shift. The results demonstrated that the highest levels of stress occur just prior to and during critical incidents, and that officers do not fully recover from that stress before leaving their shift. Overall, the results illustrate the need to consider stress reactivity and repressors in the assessment of police officer stress while clearly demonstrating the need for debriefing after critical incidents and increased training in stress management and coping strategies.

Influence of moderate prophylactic compression on sport performance.

This study examined the impact of using elasticized compression shorts on performance measures and proprioception at the hip. Thirteen healthy subjects completed 2 randomized testing sessions—one while wearing the Coreshorts compression shorts and one while not wearing the shorts. During each trial, active range of motion at the hip; joint angle replication during hip flexion, abduction, and hyperextension; leg power; agility; speed; and aerobic endurance were measured, and subjective information pertaining to the fit of the shorts was collected. The use of the prophylactic brace did not limit performance on any measure except active range of motion during hip flexion (p < 0.05). Subjective data revealed 93.3% of subjects felt the shorts were supportive, although proper fit was an issue. The present results support the use of moderate compression at and around the hip for the purpose of injury prevention. Continued research is necessary to determine the efficacy of hip bracing within an injured population and their potential prophylactic benefit for active individuals.

Electromyographic activity of the trunk stabilizers during stable and unstable bench press.

The purpose of this study was to investigate the effectiveness of instability training in the recruitment of core stabilizing muscles during dynamic multijoint movement. Surface electromyography (EMG) was measured from 6 muscles (latissimus dorsi, rectus abdominus, internal obliques, erector spinae, and soleus) while subjects performed a 9.1-kg bench press on stable and unstable surfaces. There were 4 exercises in total: (a) stable surfaces for shoulders and feet, (b) upper-body instability, (c) lower-body instability, and (d) dual instability. Five seconds of EMG were recorded during each bench press and were subsequently smoothed with root mean squares calculated for the entire time-series. A repeated-measures analysis of variance (ANOVA) was used to test overall differences between exercise conditions for each muscle. Paired equal variance t-tests with a stepwise Bonferroni correction for multiple contrasts (α = 0.05/total number of contrasts) were performed for muscles with significant repeated-measures ANOVA results. The results show significant increases in EMG with increasing instability. Specifically, the dual instability bench press resulted in the greatest mean muscle activation of the 3 stability conditions, with single instability conditions being significantly greater than the stable condition. This pattern of results is consistent with the position that performing the bench press in a progressively unstable environment may be an effective method to increase activation of the core stabilizing musculature, while the upper- and lower-body stabilizers can be activated differentially depending on the mode of instability.

Police officer physical ability testing – Re‐validating a selection criterion

The aim of this study was to determine the bona fide occupational requirements of general duty police work, and use this information to re‐validate a physical abilities test used in the police recruit selection process. A systematic random sample (n = 267) of general duty police officers completed two questionnaires: one concerning “average” duties, and one concerning the most physically demanding critical incident occurring in the 12 months prior. Of those completing the surveys, observational data were collected on every second officer, resulting in observational data collected for 121 officers, involving the recording of all physical activities and movement patterns observed throughout a ten hour shift. Data collected suggest there is a core of bona fide occupational requirements for general duty police work – walking, climbing stairs, manipulating objects, twisting/turning, pulling/pushing, running, bending, squatting and kneeling, and lifting and carrying. Many of these are involved in physical control of suspects, and can be tested using a well designed physical abilities test that simulates getting to the problem, controlling the problem, and removing the problem.

Gender differences in physiological reactions to thermal stress

Following an extensive anthropometric evaluation, thermoregulatory responses were studied in nine men and nine women who performed immersed exercise with post-exercise rest in 28°C water. During the post-exercise period esophageal temperature (Tes), oxygen consumption, heat flux and skin blood perfusion were monitored at 10s intervals, with average minute values used for calculations. The ΔTes (relative to restingTes) at which sweating abated and shivering commenced were defined as the ΔTes thresholds for the cessation of sweating and onset of shivering, respectively. No significant gender differences were evident in the sweating and shivering threshold ΔTes values, or the magnitude of the null-zone. Usingz-tests for parallelism the rates of core cooling across the null-zone were not found to differ significantly between genders, nor were the slopes of the perfusion: ΔTes responses across the null-zone or the post-threshold shivering responses (ml·kg−1·min−1·°C−1). The slope of the sweating response (measured from immersion until sweat cessation; g·m−2·min−1°C−1) was, however, significantly lower in the female than in the male samples (z = 3.93;P < 0.01). Despite the gender-related dimorphic distribution of adipose tissue, both men and women lost equal proportions of their total heat flux from central and peripheral measurement sites. Performing a standardized regression using the rate of core cooling across the null-zone as the dependent variable and gender as a dummy variable, gender and adipose tissue mass were not found to be significant factors in determining the rate of core cooling, while mass (β = 1.73;P < 0.05) and muscle mass (β = 1.86;P < 0.05) did contribute significantly to the rate of core cooling. It was concluded that, except for the quantitative differences in the sweating response, men and women respond to deviations in core temperature in a similar manner, with mass and muscle mass modifying this response.

Predicting shooting scores from physical performance data

Selecting the right people for police work is not only important for the employer, but is also in the best interest of the public. Failure to screen out individuals who cannot perform the physical duties has a large human and economic cost. The present study investigated whether physical performance and anthropometric measures can predict recruits’ handgun marksmanship. While significant correlations were found between handgun marksmanship and dominant grip strength, combined grip strength, forearm girth and second ray length, significance was only found when the genders were analyzed together. A step‐wise multiple regression could not generate an equation to predict shooting score from the available data.

Thermoregulatory responses of circum-pubertal children

AbstractPassive temperature lability of nine circumpubertal children [11.4 (1.2) years] was compared to that of nine young adult males [26.6 (5.2) years]. Each subject completed a 20-min period of exercise, followed immediately by post-exercise immersion in water at 28°C. The aim of the exercise protocol was to induce a steady rate of sweating (ESW) while the postexercise immersion period induced cooling of the core region (tympanic temperature:Tty). TheTty values (relative to rest, ΔTty) at which sweating abated and at which shivering commenced were defined as the thresholds for the cessation of sweating and onset of shivering, respectively. While there was no significant difference between the ΔTty sweating thresholds, the onset of shivering, as reflected in the oxygen uptake

Classifying children for sports participation based upon anthropometric measurement

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