Two nights of sleep deprivation with or without energy restriction does not impair the thermal response to cold

authored by
Samuel J. Oliver, Adam D. Harper Smith, Ricardo J.S. Costa, Norbert Maassen, James L.J. Bilzon, Neil P. Walsh
Abstract

Purpose: In persons completing exhaustive daily exercise, sleep and energy restriction have been highlighted as risk factors for hypothermia in cold environments. The present study therefore sought to determine the effect of sleep deprivation (SDEP), with and without energy restriction, on the thermal response to cold. Methods: In a random order, ten recreationally active men (mean ± SD: age 25 ± 6 years, body fat 17 ± 5 %) completed three 53 h trials: a control (CON: 436 min/night sleep), SDEP (0 min sleep), and sleep deprivation and energy restriction (SDEP + ER: 0 min sleep and 10 % daily energy requirements). Exhaustive exercise was completed after 5 and 29 h. After 53 h participants completed a semi-nude seated cold air test (CAT, 0 °C), for 4 h or until rectal core temperature (Tre) reached 36 °C. Results: Two nights of sleep and energy restriction did not impair the thermal response to cold (Tre, CON 36.15 ± 0.20 °C, SDEP 36.30 ± 0.15 °C, SDEP + ER 36.25 ± 0.20 °C, P = 0.25). Rewarming was also similar as indicated by 1 h post-CAT Tre (P = 0.78). In contrast, perceived thermal discomfort during the initial hour of the CAT tended to be greater after SDEP and SDEP + ER (P ≤ 0.1). Conclusion: Sleep and energy restriction, at least as evaluated within this experiment, should be considered minimal risk factors for hypothermia. The greater perception of cold discomfort at the same body temperature suggests that sleep and energy restriction may actually reduce cold injury risk, as people are likely to engage earlier in normal behavioral cold adaptation.

Organisation(s)
Institute of Sports Science
External Organisation(s)
Bangor University
Monash University
University of Bath
Type
Article
Journal
European Journal of Applied Physiology
Volume
115
Pages
2059-2068
No. of pages
10
ISSN
1439-6319
Publication date
22.10.2015
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Orthopedics and Sports Medicine, Public Health, Environmental and Occupational Health, Physiology (medical)
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Electronic version(s)
https://doi.org/10.1007/s00421-015-3184-y (Access: Closed)