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Physical Characteristics of Fast Roping in British Elite Law Enforcement Officers
Joseph Warwick1, Sarita Harris1, Hannah Ranger1
1University College London, London, UK.
Abstract:
Elite law enforcement and special forces operators around the world have a unique skill set, including some risky methods of entry into a scene of operation. With fast roping being actively utilized by this population, it is important to gain an understanding of the physical demands of the task. Thirty-seven Law Enforcement Officers (LEOs) completed five 20 ft fast rope descents onto a force platform, three in standard uniform (without kit) and two with the additional weight of operational kit (with kit). Additionally, 12 LEOs were also fitted with electromyography on their dominant arm. Landing forces with and without kit showed no significant difference. Participants with hang test time (HTT) < 35s showed significantly poorer Landing Control (LC) when descending with kit (p < 0.01). Landing control played an important role, with peak landing force significantly higher (p = 0.025) in uncontrolled landings. CMJ breaking impulse and rebound jump height are the main physical measurable predictors. However, when adjusting for body weight and kit, only rebound jump height remained predictive with marginal significance (p = 0.06) (R2 = 0.45, p = 0.008). The biceps brachii (BB) exhibited greater activation when descending with kit (p = 0.003). However, the extensor carpi radialis exhibited the greatest activation during descents in both conditions (p < 0.003). Landing impact forces were not significantly different between groups, however longer HTT correlated with more controlled descents and reduced landing forces. The ECR was observed to be the muscle with the highest activation on all descents, with only the BB increasing in kit.
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