Effect of strenuous live-fire drills on cardiovascular and psychological responses of recruit firefighters.

The study examined the effects of repeated strenuous live-fire drills on cardiovascular and psychological responses of male recruit firefighters (n = 7). Participants performed three trials of a standardized set of tasks while inside a training structure containing several live fires. Measurements of heart rate, aortic blood flow, perceived exertion, respiratory and thermal distress, reaction time, and error rate were obtained before testing, after each trial and during recovery. Heart rate increased significantly during each of the trials, reaching age-predicted maximal values. Stroke volume was significantly lower after trial 3 versus trial 1 and prevalues. Perceived exertion, respiratory distress, and thermal distress all increased, indicating greater stress following firefighting activities. Reaction time and error rate did not change significantly, but there was a tendency for more errors following trials 2 and 3 versus trial 1. The training drills resulted in considerable physiological and psychological strain, which has the potential to impair cognitive function. Firefighters are encouraged to take all possible steps to mitigate the extent of the cardiovascular strain.