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Comparison of different cooling regimes within a shortened liquid cooling/warming garment on physiological and psychological comfort during exerciseThe 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.
Document ID
Document Type
Reprint (Version printed in journal)
Leon, Gloria R. (University of Minnesota Minneapolis, MN 55455, United States)
Koscheyev, Victor S.
Coca, Aitor
List, Nathan
Date Acquired
August 23, 2013
Publication Date
January 1, 2004
Publication Information
Publication: Habitation (Elmsford, N.Y.)
Volume: 10
Issue: 1
ISSN: 1542-9660
Subject Category
Man/System Technology and Life Support
Funding Number(s)
Distribution Limits
NASA Discipline Life Sciences Technologies
Non-NASA Center