The performance during four stationary knife attacks: Implications for tactical training.

Unlabelled: With over 72,000 offenses between 2010 and 2020 in the USA, knives were the third most commonly used weapon in all violent crimes between behind personal weapons and handguns.

Purpose: Examine the performance of different stab (Thrust and overhead) and slash (Figure 8 and Reverse) knife motions to determine how long it takes to execute each motion. In addition, examine the variability in executing each motion to inform future self-defense strategies.

Methods: Twenty subjects (Females, n = 4; Males, n = 16; Height: 179.96 ± 8.66 cm; Weight: 94.99 ± 22.37 kg; Age: 36.95 ± 10.63 years) who were all active-duty law enforcement officers (LEOs) with 13.52 ± 11.23 years of LEO experience were recruited to participate in the study. Each subject completed two trials of the knife motions while wearing wearable motion sensors (ADPM) and recorded with a high-speed camera (GoPro) while using a training knife (Cold Steel).

Results: The time to complete the motions were: Thrust, 0.61 ± 0.15 s; Overhead, 0.68 ± 0.14 s; Figure 8, 1.07 ± 0.21 s; and Reverse, 0.62 ± 0.11 s. The Figure 8 motion was significantly slower than the other three motions: F (3, 57) = 101.19, p < 0.001, ηp2 = 0.84. The reliability analysis reported trivial variability and a high level of agreement: Thrust, ICCα = 0.701, SEM = 0.09 s, CV% = 15.02; Overhead, ICCα = 0.878, SEM = 0.05 s, CV% = 6.93; Figure 8, ICCα = 0.906, SEM = 0.07 s, CV% = 6.25, Reverse, ICCα = 0.420, SEM = 0.10 s, CV% = 17.31.

Discussion: Most LEOs or civilians within striking distance of someone with a knife may not be able to avoid contact from the knife attacks based on the speed knife attacks could occur.

Conclusion: The reference data provides pertinent information to update evidence-based training approaches to knife attack preparation and defense.