Physiological strain and decision making affected by different cooling tactics following live‐fire training

Abstract

Multiple factors, including different environmental, physical, and psychophysiological agents, influence firefighters’ health and safety in real fire and rescue operations. This experimental study investigated the effect of live‐fire training and cooling strategies on both physiological response and decision making. Twenty‐three healthy male firefighters performed live‐fire tasks in four separate conditions: namely rest or without cooling method (WCM), cool vest (CV), forearm immersion (FI), and cool vest and forearm immersion (CV + FI). Cooling effects of the employed interventions were evaluated based on heart rate (HR), tympanic temperature (TT), and Iowa gambling task (IGT) scores. At the end of the four experimental conditions, HR and TT increased, whereas IGT scores as a measure of decision making decreased relative to baseline. HR (beats per minute) and TT (°C) were significantly lower at the end of the experiment in the CV, FI, and CV + FI compared with the WCM conditions. There was no significant difference in Iowa scores between experimental conditions. These consequences demonstrate that live‐fire tasks are effective in raising the physiological and decision‐making responses following firefighting activities. It is concluded that CV, FI, and CV + FI were more effective than the WCM in attenuating physiological responses and decision making during live‐fire training.

Physical Exertion Partially Mitigates Task-Switching Deficits From Sleep Loss

“…Notably, we did not find evidence that physical exertion exacerbated cognitive deficits from sleep loss. Most studies show a decline in cognitive performance after simulated firefighting tasks, [17][18][19][20][21] instead of an improvement or resilience (no change) in cognitive performance. 23,24 Importantly, participants in the current study were performing under conditions of sleep loss, which impaired cognitive performance before the treadmill exercise task, and may have influenced relationships between physical exertion and cognition.…”

“…However, it was likely less physically/ emotionally demanding than other simulated firefighting tasks, such as passing through live fire, extinguishing a fire, navigating narrow/ smoky enclosures, or rescuing a victim suspended at height. [17][18][19][20][21]23,24 These simulated firefighting activities may be more likely to induce a greater degree of exhaustion and/or dehydration, which tends to worsen cognitive performance. 25,48 Thus, more research is needed to understand how the relationship between firefighting activities and different cognitive processes changes when firefighters are under conditions of insufficient sleep.…”

“…In addition, the treadmill exercise task used here incorporated elements of firefighting (ie, hot environment, heavy protective clothing, physically demanding). However, it was likely less physically/emotionally demanding than other simulated firefighting tasks, such as passing through live fire, extinguishing a fire, navigating narrow/smoky enclosures, or rescuing a victim suspended at height 17–21,23,24 . These simulated firefighting activities may be more likely to induce a greater degree of exhaustion and/or dehydration, which tends to worsen cognitive performance 25,48 .…”

“…15,16 More specifically, acute exercise tends to have some of the strongest effects on executive function tasks, and reaction time (RT) outcomes tend to be more sensitive to the effects of acute exercise than accuracy outcomes. 15,16 However, cognitive performance tends to decline [17][18][19][20][21] or show signs of a speed accuracy trade-off 22 after simulated firefighting activities (eg, fire suppression, rescue operations, live-fire drills, heat stress, smoke chambers) rather than improve 23 or remain resilient (no change 24 ). The tendency for cognition to worsen during simulated firefighting tasks may be due to an increased likelihood of exhaustion or dehydration, which has a negative effect on cognition.…”