Aerobic Fitness Assessments In Deputy Sheriff Recruits: The 20-Meter Multistage Fitness Test And 1.5-Mile Run

INTRODUCTION Aerobic fitness is often assessed during the hiring process, at the start, and throughout academy training in law enforcement recruits. The multi-stage fitness test (MSFT) is commonly used in the UK and Australia. Incorporating distances of 15-20 m, the MSFT has the advantage of providing an external pacing strategy. In contrast, in the USA the 1.5-mile run is arguably the most common aerobic assessment in law enforcement. Potential limitations of the 1.5-mile run is that recruits use an internal pacing strategy where they find a comfortable running cadence, and this assessment requires fewer direction changes. The aim of this study was to document sex differences between the 20-m MSFT (20MSFT) and 1.5-mile run in deputy sheriff recruits, and relationships between the assessments. METHODS Retrospective analysis on recruits from four academy classes (196 males, 28 females) from one agency was conducted. The 20MSFT was completed prior to academy training. The 1.5-mile run was completed in the first week of academy. Between-sex comparisons in the 20MSFT and 1.5-mile run was conducted with independent samples t-tests (p ≤ 0.05). Pearson’s correlations and linear regression scatter plots calculated relationships between 20MSFT shuttle score and 1.5-mile run time (the sexes were analysed separately). RESULTS There were no significant between-sex differences (p = 0.06) for the 20MSFT shuttles (♂ = 63 ± 19; ♀ = 56 ± 14), but there was for 1.5-mile run time (p < 0.01; ♂ = 11:21 ± 1:16 min:sec; ♀ = 12:22 ± 1:06 min:sec). 20MSFT shuttles had moderate (r = -0.42) and large (r = -0.60) relationships with 1.5- mile run time for males and females, respectively. The r2 values from the regression equations for males (r2 = 0.18) and females (r2 = 0.36) was relatively low. CONCLUSIONS The between-sex differences in the 20MSFT appeared less than that for the 1.5-mile run, although this may have been influenced by the disparate sample size for each sex. Even with significant relationships between the assessments, the predictive relationships were low. This could be because the 20MSFT induces a higher running intensity via speed increases and greater requirement for continued direction changes, which may limit transferability between the two assessments. Further investigation of the 20MSFT is required as to its applicability to indicate academy graduation or separation, and relationships with law enforcement-specific tasks.