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Effect of Cardiorespiratory Fitness Level on Physiological Responses and Task Performance During a High-Rise
Richard Daniel Mark Stevenson1, Joseph Warwick, James Lee John Bilzon
1From the Department for Health, University of Bath, Bath, UK (R.D.M.S., J.L.J.B.); and University College London, London, UK (W.J.).
Objectives:
To determine the impact of cardiorespiratory fitness (CRF) on physiological and performance outcomes during a 120-m vertical high-rise ascent in firefighters with CRF levels at or above (higher-fit) and below (lower-fit [LF]) the national recommended minimum physical employment standard (V˙O 2 max 42.3 mL·kg -1 ·min -1 ).
Methods:
Twenty-eight firefighters completed two high-rise firefighting trials (continuous and discontinuous ascent with predetermined 1-minute rest breaks). Task time, heart rate, ratings of perceived exertion, core body temperature, and thermal comfort were recorded at predetermined elevations.
Results:
Task time was significantly longer in both trials for the LF group. Ratings of perceived exertion and thermal comfort were also significantly higher in the LF group, with three times more LF firefighters being unable to complete the ascent without sounding their low-air alarm.
Conclusions:
Higher CRF improves performance and efficiency during stair-climbing in simulated high-rise firefighting tasks.
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