caa a22 4500 467941157 CHVBK 20180406153013.0 cr unu---uuuuu 170328e20060301xx s 000 0 eng 10.1007/s00421-005-0063-y doi (NATIONALLICENCE)springer-10.1007/s00421-005-0063-y Safe cooling limits from exercise-induced hyperthermia [Elektronische Daten] [C.I. Proulx, M.B. Ducharme, G.P. Kenny] We evaluated the cooling rate of hyperthermic subjects, as measured by three estimates of deep core temperatures (esophageal, rectal and aural canal temperatures), during immersion in a range of water temperatures. The objective of the study was to compare the three indices of core temperature and define safe cooling limits when using rectal temperature to avoid the development of hypothermia. On 4 separate days, seven subjects (four males, three females) exercised for 45.4±4.1min at 65% $$ \ifmmode\expandafter\dot\else\expandafter\.\fi{V}{\text{O}}_{{2\max }} $$ at an ambient temperature of 39°C, RH: 36.5%, until rectal temperature (T re) increased to 40.0°C (39.5°C for two subjects). Following exercise, the subjects were immersed in a circulated water bath controlled at 2, 8, 14 and 20°C until T re returned to 37.5°C. When T re reached normothermia during the cooling period (37.5±0.05°C), both esophageal (T es) (35.6±1.3°C) and aural canal (T ac) (35.9±0.9°C) temperatures were approaching or reaching hypothermia, particularly during immersion in 2°C water (T es=34.5±1.2°C). On the basis of the heat loss data, the heat gained during the exercise was fully eliminated after 5.4±1.5, 7.9±2.9, 10.4±3.8 and 13.1±2.8min of immersion in 2, 8, 14 and 20°C water, respectively, with the coldest water showing a significantly faster cooling rate. During the immersion in 2°C water, a decrease of only 1.5°C in T re resulted in the elimination of 100% of the heat gained during exercise without causing hypothermia. This study would therefore support cooling the core temperature of hyperthermic subjects to a rectal temperature between 37.8°C (during immersion in water >10°C) and 38.6°C (during immersion in water <10°C) to eliminate the heat gained during exercise without causing hypothermia. Springer-Verlag, 2005 Whole-body cooling nationallicence Indices of core temperature nationallicence Heat stress nationallicence Heat illness nationallicence Cold-water bath nationallicence Proulx C.I. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut Ducharme M.B. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut Kenny G.P. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut European Journal of Applied Physiology Springer-Verlag 96/4(2006-03-01), 434-445 1439-6319 96:4<434 2006 96 421 https://doi.org/10.1007/s00421-005-0063-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00421-005-0063-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Proulx C.I. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut NATIONALLICENCE 700 1- Ducharme M.B. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut NATIONALLICENCE 700 1- Kenny G.P. Laboratory of Human Bioenergetics and Environmental Physiology, University of Ottawa, Montpetit Hall, Room 367, 125 University Ave., K1N 6N5, Ottawa, Canada aut NATIONALLICENCE 773 0- European Journal of Applied Physiology Springer-Verlag 96/4(2006-03-01), 434-445 1439-6319 96:4<434 2006 96 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer