A1 Journal article (refereed)
Endurance Capacity Impairment in Cold Air Ranging from Skin Cooling to Mild Hypothermia (2024)


Wallace, P. J., Hartley, G. L., Nowlan, J. G., Ljubanovich, J., Sieh, N., Taber, M. J., Gagnon, D. D., & Cheung, S. S. (2024). Endurance Capacity Impairment in Cold Air Ranging from Skin Cooling to Mild Hypothermia. Journal of Applied Physiology, 136(1), 58-69. https://doi.org/10.1152/japplphysiol.00663.2023


JYU authors or editors


Publication details

All authors or editorsWallace, Phillip J.; Hartley, Geoffrey L.; Nowlan, Josh G.; Ljubanovich, Johnathan; Sieh, Nina; Taber, Michael J.; Gagnon, Dominique D.; Cheung, Stephen S.

Journal or seriesJournal of Applied Physiology

ISSN8750-7587

eISSN1522-1601

Publication year2024

Publication date09/11/2023

Volume136

Issue number1

Pages range58-69

PublisherAmerican Physiological Society

Publication countryUnited States

Publication languageEnglish

DOIhttps://doi.org/10.1152/japplphysiol.00663.2023

Publication open accessNot open

Publication channel open access

Publication is parallel published (JYX)https://jyx.jyu.fi/handle/123456789/92145


Abstract

Introduction: We tested the effects of cold air (0°C) exposure on endurance capacity to different levels of cold strain ranging from skin cooling to core cooling of ∆-1.0°C.
Methods: Ten males completed cycling time-to-exhaustion (TTE) at 70% of their peak power output following: i) 30-min of exposure to 22°C thermoneutral air (TN), ii) 30-min exposure to 0°C air leading to a cold shell (CS), iii) 0°C air exposure causing mild hypothermia of -0.5°C from baseline rectal temperature (HYPO-0.5°C), and iv) 0°C air exposure causing mild hypothermia of -1.0°C from baseline rectal temperature (HYPO-1.0°C). The latter three conditions tested TTE in 0°C air.
Results: Core temperature and seven-site mean skin temperature at the start of the TTE were: TN (37.0 ± 0.2°C, 31.2 ± 0.8°C), CS (37.1 ± 0.3°C, 25.5 ± 1.4°C), HYPO-0.5°C (36.6 ± 0.4°C, 22.3 ± 2.2°C), HYPO-1.0°C (36.4 ± 0.5°C, 21.4 ± 2.7°C). There was a significant condition effect (p≤0.001) for TTE, where TTE declined from TN (23.75 ± 13.75 min) to CS (16.22 ± 10.30 min, ∆-30.9 ± 21.5%, p=0.055), HYPO-0.5°C (8.50 ± 5.23 min, ∆-61.4 ± 19.7, p≤0.001), and HYPO-1.0°C (6.50 ± 5.60 min, ∆-71.6 ± 16.4%, p≤0.001). Furthermore, participants had a greater endurance capacity in CS compared to HYPO-0.5°C (p=0.046), and HYPO-1.0°C (p=0.007), with no differences between HYPO-0.5°C and HYPO-1.0°C (p=1.00).
Conclusion: Endurance capacity impairment at 70% peak power output occurs early in cold exposure with skin cooling and inadequate clothing, with significantly larger impairments with mild hypothermia up to ∆-1.0°C.


Keywordscoldenduranceperformance (capacity)hypothermiabody temperaturetemperatureexposureskinclothes

Free keywordscore cooling; mild hypothermia; endurance capacity; cold strain; heat debt


Contributing organizations


Ministry reportingYes

Reporting Year2023

Preliminary JUFO rating2


Last updated on 2024-25-03 at 09:37