Abstract
AIMS: Exposure to artificial gravity (AG) at different G loads and durations on human centrifuges has been shown to improve orthostatic tolerance in men. However, the effects on women and of an individual-specific AG training protocol on tolerance are not known.
METHODS: We examined the effects of 90 minutes of AG vs. 90 minutes of supine rest on the orthostatic tolerance limit (OTL), using head up tilt and lower body negative pressure until presyncope of 7 men and 5 women. Subjects were placed in the centrifuge nacelle while instrumented and after one-hour they underwent either: 1) AG exposure (90 minutes) in supine position [protocol 1, artificial gravity exposure], or 2) lay supine on the centrifuge for 90 minutes in supine position without AG exposure [protocol 2, control]. The AG training protocol was individualized, by first determining each subject's maximum tolerable G load, and then exposing them to 45 minutes of ramp training at sub-presyncopal levels.
RESULTS: Both sexes had improved OTL (14 minutes vs 11 minutes, p < 0.0019) following AG exposure. When cardiovascular (CV) variables at presyncope in the control test were compared with the CV variables at the same tilt-test time (isotime) during post-centrifuge, higher blood pressure, stroke volume and cardiac output and similar heart rates and peripheral resistance were found post-centrifuge.
CONCLUSIONS: These data suggest a better-maintained central circulating blood volume post-centrifugation across gender and provide an integrated insight into mechanisms of blood pressure regulation and the possible implementation of in-flight AG countermeasure profiles during spaceflights.
Document Type
Article
Publication Date
5-28-2015
Digital Object Identifier (DOI)
http://dx.doi.org/10.1371/journal.pone.0125780
Funding Information
The European Space Agency’s CORA-GBF program supported this study. Land Steiermark, Austria, also supported Dr. Nandu Goswami. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Repository Citation
Goswami, Nandu; Evans, Joyce; Schneider, Stefan; von der Wiesche, Melanie; Mulder, Edwin; Rössler, Andreas; Hinghofer-Szalkay, Helmut; and Blaber, Andrew P., "Effects of Individualized Centrifugation Training on Orthostatic Tolerance in Men and Women" (2015). Biomedical Engineering Faculty Publications. 9.
https://uknowledge.uky.edu/cbme_facpub/9
S1 File. Data for Fig 1.
journal.pone.0125780.s002.XLS (30 kB)
S2 File. Data for Fig 2.
Notes/Citation Information
Published in PLOS One, v. 10, no. 5, article e0125780, p. 1-13.
© 2015 Goswami et al.
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited