Oliver Samuel J, Harper Smith Adam D, Costa Ricardo J S, Maassen Norbert, Bilzon James L J, Walsh Neil P
Extremes Research Group, Bangor University, Bangor, LL57 2PZ, UK.
Department of Nutrition and Dietetics, Monash University, Melbourne, Australia.
Eur J Appl Physiol. 2015 Oct;115(10):2059-68. doi: 10.1007/s00421-015-3184-y. Epub 2015 May 21.
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.
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 (T re) reached 36 °C.
Two nights of sleep and energy restriction did not impair the thermal response to cold (T re, 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 T re (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).
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.
在完成每日力竭运动的人群中，睡眠和能量限制已被视为寒冷环境下体温过低的风险因素。因此，本研究旨在确定睡眠剥夺（SDEP）在有或没有能量限制的情况下对寒冷热反应的影响。
10名有运动习惯的男性（平均±标准差：年龄25±6岁，体脂17±5%）按随机顺序完成了三项53小时的试验：对照组（CON：每晚睡眠436分钟）、睡眠剥夺组（SDEP：0分钟睡眠）和睡眠剥夺加能量限制组（SDEP + ER：0分钟睡眠且摄入10%的每日能量需求）。在5小时和29小时后完成力竭运动。53小时后，参与者完成了一项半裸坐姿冷空气测试（CAT，0°C），持续4小时或直到直肠核心温度（Tre）达到36°C。
两晚的睡眠和能量限制并未损害对寒冷的热反应（Tre，CON组为36.15±0.20°C，SDEP组为36.30±0.15°C，SDEP + ER组为36.25±0.20°C，P = 0.25）。CAT后1小时的Tre表明复温情况也相似（P = 0.78）。相比之下，在CAT最初一小时内，SDEP组和SDEP + ER组的热不适感受倾向于更强（P≤0.1）。
至少在本实验所评估的范围内，睡眠和能量限制应被视为体温过低的最小风险因素。在相同体温下对寒冷不适的更强感受表明，睡眠和能量限制实际上可能会降低寒冷损伤风险，因为人们可能会更早地进行正常的行为性寒冷适应。
