Leon Gloria R, Koscheyev Victor S, Coca Aitor, List Nathan
Department of Psychology, University of Minnesota, Minneapolis, MN 55455, USA.
Habitation (Elmsford). 2004;10(1):61-7. doi: 10.3727/154296604774808919.
The aim of this study was to compare the effectiveness of different cooling regime intensities to maintain physiological and subjective comfort during physical exertion levels comparable to that engaged in during extravehicular activities (EVA) in space. We studied eight subjects (six males, two females) donned in our newly developed physiologically based shortened liquid cooling/warming garment (SLCWG). Rigorous (condition 1) and mild (condition 2) water temperature cooling regimes were compared at physical exertion levels comparable to that performed during EVA to ascertain the effectiveness of a lesser intensity of cooling in maintaining thermal comfort, thus reducing energy consumption in the portable life support system. Exercise intensity was varied across stages of the session. Finger temperature, rectal temperature, and subjective perception of overall body and hand comfort were assessed. Finger temperature was significantly higher in the rigorous cooling condition and showed a consistent increase across exercise stages, likely due to the restriction of heat extraction because of the intensive cold. In the mild cooling condition, finger temperature exhibited an overall decline with cooling, indicating greater heat extraction from the body. Rectal temperature was not significantly different between conditions, and showed a steady increase over exercise stages in both rigorous and mild cooling conditions. Ratings of overall comfort were 30% higher (more positive) and more stable in mild cooling (p<0.001). The mild cooling regime was more effective than rigorous cooling in allowing the process of heat exchange to occur, thus maintaining thermal homeostasis and subjective comfort during physical exertion.
本研究的目的是比较不同冷却方式强度在与太空舱外活动（EVA）相当的体力消耗水平下维持生理和主观舒适度的效果。我们研究了八名受试者（六名男性，两名女性），他们穿着我们新开发的基于生理原理的缩短型液体冷却/加热服装（SLCWG）。在与EVA期间相当的体力消耗水平下，比较了严格（条件1）和温和（条件2）水温冷却方式，以确定较低强度的冷却在维持热舒适度方面的有效性，从而降低便携式生命支持系统中的能量消耗。运动强度在实验过程的不同阶段有所变化。评估了手指温度、直肠温度以及对全身和手部舒适度的主观感受。在严格冷却条件下，手指温度显著更高，并且在运动阶段持续上升，这可能是由于强烈的寒冷限制了热量散发。在温和冷却条件下，手指温度随着冷却总体呈下降趋势，表明从身体散发的热量更多。两种条件下直肠温度没有显著差异，并且在严格和温和冷却条件下，运动阶段直肠温度均呈稳定上升。温和冷却条件下总体舒适度评分高30%（更积极）且更稳定（p<0.001）。在体力消耗过程中，温和冷却方式比严格冷却方式在允许热交换过程发生方面更有效，从而维持热稳态和主观舒适度。
