The steady-state load of five firefighting tasks

Abstract

ORCID for Asgeir Mamen: 0000-0002-4316-7455Word count: 3350 words JOSE: http://www.editorialmanager.com/ijose/default.aspx 2 Abstract Purpose. Physiologic demands of five common tasks in firefighting have been examined. Methods.Eight male volunteers, being dressed up as smoke divers (+21 kg extra load), carried out the following tasks at constant pace for 5 min: Walking at 1.4 m·s -1 , walking (all walks at the same speed) while carrying a 10 kg ladder, walking carrying two hose packs of 16 kg together, walking carrying a 32 kg spreader tool, finally climbing up and down a ladder at preset pace. A 5 min break separated each exercise. Heart rate, O 2 -uptake and ventilation were measured continuously, and blood lactate concentration was recorded after each task. Results. The end-exercise heart rate rose from 108 to 180 bpm from first to last task, blood lactate concentration rose from 1 to 7 mmol·L -1 , O 2 -uptake rose from 19 to 48 ml·kg -1 ·min -1 , and ventilation rose from 38 to 124 L·min -1 . Discussion. Walking was an easy task even when dressed up as a smoke diver. Adding loads increased demands; ladder climbing taxed >90% of the subjects' aerobic power. Conclusions. The physiologic demands varied considerably between different tasks.

The Validity and Reliability of a Treadmill Test for Structural Firefighter Applicants

“…Average V˙O2 during simulated fire-rescue work from each of 12 previously published studies, 3,5–7,9,11–17 is displayed in Figure 2. The mean of these values was 2.82 ± 0.32 L·min –1 .…”

“…For both treadmill test outcomes described above (average V˙O2 and V˙O2peak), we compared the mean values from the sample of 260 test records from our laboratory to the mean values reported by the other authorities. Confidence intervals (95%) were calculated for our data (n = 260) and the data from other sources (n = 12 studies for average V˙O2, 3,5,7,9,11–17 and n = 8 for recommended V˙O2peak 3–10 ) .…”

“…Early approaches to documenting aerobic demand 4,19 were limited to measuring the oxygen uptake during single tasks using the Douglas Bag method. Advancements in ambulatory spirometry instrumentation allowed measurement during scenarios that more accurately replicated the typical combination of activities during initial attack responses of structural firefighting (eg lifting, carrying, climbing, striking, dragging) 5–7,9–17 . Review of the relevant literature reveals that fire-rescue work requires relatively high rates of oxygen uptake (up to 3 L·min –1 ) for relatively short periods of time (typically up to approximately 2° min) 1,2 .…”

“…Evaluations of cardiorespiratory endurance are important for several reasons. First, work capacity, primarily supported by aerobic metabolism, has historically been considered an important part of physiological readiness for arduous work 1–4,17,19 . Safe and effective fire-rescue work requires an appropriate level of cardiorespiratory endurance for the duration of time-sensitive fire-rescue emergencies 8 .…”

Urinary Proteomics of Simulated Firefighting Tasks and Its Relation to Fitness Parameters

“…Therefore, many studies designed simulated firefighting exercises according to specific research aims and measured physiological responses and physical performance of firefighters during simulated rescue tasks [13][14][15]. These studies mainly concentrated on cardiorespiratory fitness and energy requirement or cost of a simulated intervention [16], and the heart rate [17], oxygen uptake [16,18], expiratory ventilation [19], blood lactate concentration [20], and rating of perceived exertion (RPE) [21] were usually measured. Although these evaluation indexes could reflect some specific physiological alterations in simulated firefighting tasks, it is difficult to give a full picture of how simulated rescues may affect human physiology.…”