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Exercise with prebreathe appears to increase protection from decompression sickness: Preliminary findingsExtravehicular activity (EVA) from the Space Shuttle involves one hour of prebreath with 100% oxygen, decompression of the entire Shuttle to 10.2 psia for at least 12 hours, and another prebreath for 40 minutes before decompression to the 4.3 psia suit pressure. We are investigating the use of a one-hour prebreathe with 100% oxygen beginning with a ten-minute strenuous exercise period as an alternative for the staged decompression schedule described above. The 10-minute exercise consists of dual-cycle ergometry performed at 75% of the subject's peak oxygen uptake to increase denitrogenation efficiency by increasing ventilation and perfusion. The control exposures were preceded by a one-hour prebreathe with 100% oxygen while resting in a supine position. The twenty-two male subjects were exposed to 4.3 psia for 4 hours while performing light to moderate exercise. Preliminary results from 22 of the planned 26 subjects indicate 76% DCS following supine, resting prebreathe and 38% following prebreathe with exercise. The staged decompression schedule has been shown to result in 23% DCS which is not significantly different from the exercise-enhanced prebreathe results. Prebreathe including exercise appears to be comparable to the protection afforded by the more lengthy staged decompression schedule. Completion of the study later this year will enable planned statistical analysis of the results.
Document ID
Document Type
Conference Paper
Webb, James T.
(Krug Life Sciences, Inc. San Antonio, TX, United States)
Fischer, Michele D.
(Krug Life Sciences, Inc. San Antonio, TX, United States)
Heaps, Cristine L.
(Krug Life Sciences, Inc. San Antonio, TX, United States)
Pilmanis, Andrew A.
(Krug Life Sciences, Inc. San Antonio, TX, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1994
Publication Information
Publication: NASA. Johnson Space Center, Seventh Annual Workshop on Space Operations Applications and Research (SOAR 1993), Volume 2
Subject Category
Aerospace Medicine
Accession Number
Funding Number(s)
CONTRACT_GRANT: F33615-92-C-0018
CONTRACT_GRANT: F33615-89-C-0603
Distribution Limits
Work of the US Gov. Public Use Permitted.
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