Τίτλος:
Heat acclimation does not modify autonomic responses to core cooling and the skin thermal comfort zone
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Exercise heat acclimation (HA) is known to magnify the sweating response by virtue of a lower threshold as well as increased gain and maximal capacity of sweating. However, HA has been shown to potentiate the shivering response in a cold-air environment. We investigated whether HA would alter heat loss and heat production responses during water immersion. Twelve healthy male participants underwent a 10-day HA protocol comprising daily 90-min controlled-hyperthermia (target rectal temperature, Tre 38.5 °C) exercise sessions. Preceding and following HA, the participants performed a maximal exercise test in thermoneutral conditions (ambient temperature 23 °C, relative humidity 50%) and were, following exercise, immersed in 28 °C water for 60 min. Thermal comfort zone (TCZ) was also assessed with participants regulating the temperature of a water-perfused suit during heating and cooling. Baseline pre-immersion Tre was similar pre- and post-HA (pre: 38.33 ± 0.33 °C vs post: 38.12 ± 0.36 °C, p = 0.092). The Tre cooling rate was identical pre-to post-HA (−0.03 ± 0.01 °C·min−1, p = 0.31), as was the vasomotor response reflected in the forearm-fingertip temperature difference. Shivering thresholds (p = 0.43) and gains (p = 0.61) were not affected by HA. TCZ was established at similar temperatures, with the magnitude in regulated water temperature being 7.6 (16.3) °C pre-HA and 5.1 (24.7) °C post-HA (p = 0.65). The present findings suggest that heat production and heat loss responses during whole body cooling as well as the skin thermal comfort zone remained unaltered by a controlled-hyperthermia HA protocol. © 2020 Elsevier Ltd
Συγγραφείς:
Sotiridis, A.
Ciuha, U.
Debevec, T.
Mekjavic, I.B.
Περιοδικό:
Journal of Thermal Biology
Εκδότης:
Elsevier Ireland Ltd
Λέξεις-κλειδιά:
water, adult; Article; controlled study; cooling; environmental temperature; exercise; finger; forearm; heat acclimatization; heat loss; heating; human; human experiment; humidity; hyperthermia; male; normal human; physical parameters; rectal temperature; shivering; skin temperature; thermal comfort zone; thermogenesis; vasomotor reflex; water immersion; autonomic nervous system; heat tolerance; physiology; procedures; skin temperature, Adult; Autonomic Nervous System; Humans; Male; Physical Conditioning, Human; Shivering; Skin Temperature; Thermotolerance
DOI:
10.1016/j.jtherbio.2020.102602
