Purpose: Law enforcement cadets (LECs) undergo subject control technique training that may expose them to repetitive head impacts recorded as head acceleration events (HAEs) using instrumented mouthguards. Prior research suggests that sex and/or gender differences in HAE frequency and magnitude vary by sport. This study aimed to examine sex differences in HAE exposure among LECs during training.
Methods: We collected HAEs from 82 civilian LECs (16 females, mean age = 30 ± 9 years) using instrumented mouthguards. We compared peak linear acceleration (PLA) and peak rotational velocity (PRV) of HAEs > 5 g between sexes using a mixed-effects linear model, with sex and cohort as fixed-effect predictors and a random intercept for subject to account for repeated HAEs within individuals. Additionally, we assessed sex differences in the number of HAEs per athlete exposure using a negative binomial regression controlling for cohort.
Results: PLA was lower in female than male cadets (e.g., median PLA: females = 10.9 g, males = 12.3 g, p < 0.001). However, there were no statistically significant sex differences in the number of HAEs per athlete exposure (e.g., median: females = 10, males = 14, p = 0.169) or PRV (e.g., median PRV: females = 7.4 rad/s, males = 7.9 rad/s, p = 0.110).
Conclusions: Overall, sex differences in HAE frequency and magnitude during subject control technique trainings were minimal. When differences were observed, female cadets exhibited less frequent and less severe HAEs than male cadets. This finding suggests that current training practices, including sex- and/or skill-matched pairing, may effectively reduce HAE exposure risk to females.
Keywords: Combat training; Concussion; Police; Repetitive head impacts; Risk factors.
© 2025. The Author(s).