The development of orthostatic hypotension and syncopal symptoms in 30-40% of astronauts following spaceflight despite exaggerated compensatory elevations in heart rate provides fundamental evidence that the capacity of cardiovascular mechanisms responsible for blood pressure regulation has been compromised. It is clear that some alterations in cardiovascular function during exposure to microgravity can adversely affect orthostatic stability and performance of physical work during and immediately after return to earth. With the evolution of the Space Shuttle, astronauts are required to be orthostatically and physically functional to safely pilot a spacecraft back to earth as well as be prepared for the possibility of an emergency egress. this concern will take on greater proportions when future space missions include prolonged inhabitation of orbiting space stations and voyages to planetary stations requiring periodic movement into and out of various gravitational environments. The possibility that a pilot might become incapable of tolerating head-to-foot G forces during reentry and lose functional consciousness at this critical time is of concern and has sparked interest in understanding and counteracting this problem. Because of its immediate impact on operational performance, effective management of functional problems associated with cardiovascular adaptation of microgravity probably represents one of the most important concerns and challenges for future human spaceflight. Development of effective and efficient countermeasures against postflight blood pressure dysfunction and orthostatic instability has therefore become a primary emphasis of the space life sciences research effort.
Exercise Countermeasure for Spaceflight
1995
20 pages
Report
No indication
English
Astronautics , Stress Physiology , Space flight , Exercise (Physiology) , Functions , Orbits , Stability , Spacecraft , Emergencies , Management , Impact , Exposure(General) , Capacity(Quantity) , Humans , Signs and symptoms , Efficiency , Space sciences , Weightlessness , Earth(Planet) , Cardiovascular system , Instability , Space missions , Countermeasures , Consciousness , Blood pressure , Pressure regulators , Astronauts , Space biology , Hypotension , Orthostatism , Reprints
Contextual adaptation as a spaceflight neurovestibular countermeasure
British Library Conference Proceedings | 2001
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