Determining the Changes in Law Enforcement Recruit Aerobic Fitness Using the 2.4-km Run and 20-m Multistage Fitness Test. Does the Type of Test Matter?

Campbell, P, Maupin, D, Lockie, RG, Dawes, JJ, Simas, V, Canetti, E, Schram, B, and Orr, R. Determining the changes in law enforcement recruit aerobic fitness using the 2.4-km run and 20-m multistage fitness test. Does the type of test matter? J Strength Cond Res 38(6): 1111-1117, 2024 - Aerobic fitness is linked with academy graduation, employment, and the long-term health of law enforcement officers and is often used as a training outcome. However, different tests can be used, and aerobic improvements may differ according to the test used. The aim of this study was to determine whether recruits improved to a greater extent in 1 aerobic test compared with the other. Retrospective data from 5 law enforcement recruit cohorts (males = 741; females = 353) who underwent 18 weeks of academy training were analyzed. Initial 20-m multistage fitness test (20MSFT) and 2.4-km run assessments were completed during weeks 4 and 5 of training, with final testing completed during weeks 16 and 17, respectively. A repeated-measures analysis of variance (p < 0.05) with a Bonferroni post hoc analysis determined changes in aerobic fitness in the 20MSFT and 2.4-km run between male and female recruits. A mean difference of 9.27 (95% confidence intervals [CI] 14.8-10.9; d = 0.63; p < 0.001) shuttle increase in 20MSFT performance and 20.1 (95% CI 16.0-24.2; d = 0.49; p < 0.001) second improvement in 2.4-km run time were demonstrated when averaged across sex, yielding a larger performance improvement for the 20MSFT compared with the 2.4-km run. Conversely, there was a smaller magnitude of change in aerobic fitness between male recruits and female recruits for the 20MSFT (d = 0.47) compared with the 2.4-km run (d = 0.50). The findings indicate that current academy training results in improvements to aerobic fitness and to a greater magnitude in the 20MSFT compared with the 2.4-km run. These results may affect policy considerations for law enforcement agencies regarding aerobic test selection.