RESUMEN
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 (VËO 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.
Asunto(s)
Capacidad Cardiovascular , Bomberos , Frecuencia Cardíaca , Esfuerzo Físico , Análisis y Desempeño de Tareas , Humanos , Masculino , Capacidad Cardiovascular/fisiología , Adulto , Frecuencia Cardíaca/fisiología , Esfuerzo Físico/fisiología , Temperatura Corporal/fisiología , Femenino , Rendimiento Laboral , Consumo de Oxígeno/fisiología , Persona de Mediana EdadRESUMEN
OBJECTIVE: The aim of the study is to determine the physiological effects of breathing apparatus and ascent strategies during a simulated 120-m vertical high-rise firefighting ascent. METHODS: Twenty-eight firefighters completed four high-rise firefighting trials wearing standard- or extended-duration breathing apparatus with continuous ascent (SDBA-C/EDBA-C) or with breaks (SDBA-B/EDBA-B). Task time, heart rate, ratings of perceived exertion, core body temperature, and thermal comfort were recorded at predetermined elevations. RESULTS: Task time took significantly longer during the EDBA-C compared with SDBA-C trial. Heart rate (at 40, 80, and 100 m) was significantly lower in trials following breaks compared with the continuous trials. Core body temperature rose by 0.11°C every 10 m of ascent. During the SDBA trials, 89% to 96% of firefighters activated their low air alarm compared with only 7% in EDBA. CONCLUSIONS: Firefighters should wear EDBA beyond 80 m of ascent and are encouraged to take regular breaks.