Rotation at 30 RPM about the A axis after 6 hours in the 10 degree head-down position: effect on susceptibility to motion sickness.
Ashton Graybiel, James R. Lackner · PubMed · 1979
Intraindividual differences in susceptibility to motion sickness were measured in 14 subjects for two conditions of rotation at 30 rpm in the 10 degree head-down position. In one condition, subjects were in the 10 degree head-down position for 6 h prior to the onset of rotation; in the other condition, the delay was only 15 min. In both conditions, there were changes in vital capacity, indicating a redistribution of movable body fluids. Subjects tended to be less susceptible to motion sickness when they were recumbent for 6 h prior to rotation. These results are countervidence for the hypothesis that shifts of body fluid are responsible in large part for the motion sickness elicited in orbital space flight.