| | COUNTERMEASURES TO LONG-DURATION SPACEFLIGHT |
 | | Over the course of 38 years of progressively longer spaceflights, numerous adjustments to the operations of the human body have been documented. |
 | | Roughly 2/3rds to 3/4ths of Shuttle astronauts suffer from SMS to varying degrees in the first 2 days of spaceflight; symptoms of dizziness, sweating, nausea and vomiting resolve spontaneously, usually within 48 hours of entering space, but can be so debilitating that no EVAs or delicate maneuvers are planned during this period. |
 | | As discussed in Aerospace Medicine 101: Adaptations to Spaceflight, microgravity negates the bodys hydrostatic column: gravity no longer pools fluids in the lower extremities, and both intracellular and extracellular fluids rapidly redistribute evenly, shifting to the upper body and head (similar to hanging upside-down on a gym bar). |
| chapters.marssociety.org /usa/oh/aero3.htm (2056 words) |