Grace E Vincent1,2,3, Sally Ferguson4,5,6, Brianna Larsen5,6,7, Nicola D Ridgers6, Rod Snow6, Brad Aisbett5,6. 1. Appleton Institute, Central Queensland University, 44 Greenhill Road, Wayville, SA, 5034, Australia. g.vincent@cqu.edu.au. 2. Bushfire Co-Operative Research Centre, East Melbourne, 3002, Australia. g.vincent@cqu.edu.au. 3. School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition (IPAN), Deakin University, Geelong, Australia. g.vincent@cqu.edu.au. 4. Appleton Institute, Central Queensland University, 44 Greenhill Road, Wayville, SA, 5034, Australia. 5. Bushfire Co-Operative Research Centre, East Melbourne, 3002, Australia. 6. School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition (IPAN), Deakin University, Geelong, Australia. 7. Griffith Sports Physiology, School of Allied Health Sciences, Griffith University, Gold Coast, QLD, Australia.
Abstract
PURPOSE: To examine the effects of sleep restriction on firefighters' physical task performance, physical activity, and physiological and perceived exertion during simulated hot wildfire conditions. METHODS:31 firefighters were randomly allocated to either the hot (n = 18, HOT; 33 °C, 8-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Intermittent, self-paced work circuits of six firefighting tasks were performed for 3 days. Firefighters self-reported ratings of perceived exertion. Heart rate, core temperature, and physical activity were measured continuously. Fluids were consumed ad libitum, and all food and fluids consumed were recorded. Urine volume and urine specific gravity (USG) were analysed and sleep was assessed using polysomnography (PSG). RESULTS: There were no differences between the HOT and HOT + SR groups in firefighters' physical task performance, heart rate, core temperature, USG, or fluid intake. Ratings of perceived exertion were higher (p < 0.05) in the HOT + SR group for two of the six firefighting tasks. The HOT group spent approximately 7 min more undertaking moderate physical activity throughout the 2-h work circuits compared to the HOT + SR group. CONCLUSION: Two nights of sleep restriction did not influence firefighters' physical task performance or physiological responses during 3 days of simulated wildfire suppression. Further research is needed to explore firefighters' pacing strategies during real wildfire suppression.
RCT Entities:
PURPOSE: To examine the effects of sleep restriction on firefighters' physical task performance, physical activity, and physiological and perceived exertion during simulated hot wildfire conditions. METHODS: 31 firefighters were randomly allocated to either the hot (n = 18, HOT; 33 °C, 8-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Intermittent, self-paced work circuits of six firefighting tasks were performed for 3 days. Firefighters self-reported ratings of perceived exertion. Heart rate, core temperature, and physical activity were measured continuously. Fluids were consumed ad libitum, and all food and fluids consumed were recorded. Urine volume and urine specific gravity (USG) were analysed and sleep was assessed using polysomnography (PSG). RESULTS: There were no differences between the HOT and HOT + SR groups in firefighters' physical task performance, heart rate, core temperature, USG, or fluid intake. Ratings of perceived exertion were higher (p < 0.05) in the HOT + SR group for two of the six firefighting tasks. The HOT group spent approximately 7 min more undertaking moderate physical activity throughout the 2-h work circuits compared to the HOT + SR group. CONCLUSION: Two nights of sleep restriction did not influence firefighters' physical task performance or physiological responses during 3 days of simulated wildfire suppression. Further research is needed to explore firefighters' pacing strategies during real wildfire suppression.
Authors: Hugh H K Fullagar; Sabrina Skorski; Rob Duffield; Daniel Hammes; Aaron J Coutts; Tim Meyer Journal: Sports Med Date: 2015-02 Impact factor: 11.136
Authors: Charlotte C Gupta; Sally A Ferguson; Brad Aisbett; Michelle Dominiak; Stephanie E Chappel; Madeline Sprajcer; Hugh H K Fullagar; Saman Khalesi; Joshua H Guy; Grace E Vincent Journal: Nutrients Date: 2020-04-21 Impact factor: 5.717