Evaluation Of Cardiovascular Autonomic Regulation Under Various Gravitational Stresses In Humans

Current aerospace technology not only makes human activity limit expanded, but also exposes human subjects to extreme variations in gravitational forces ranging from zero during space travel to as much as nine-times normal during operation of high-performance military aircraft. As a result, it brings some new gravitational physiological problems for the aerospace research: +Gz-induced loss of consciousness (G-LOC ) has become the major cause of threat of flying safety during today's sustained aerial combat maneuvering. Removal of the normal head-to-foot gravity vector due to space travel often causes "cardiovascular deconditioning", which is manifested by reduced exercise capacity and orthostatic intolerance on return to upright posture on earth. The mechanism responsible for this phenomenon has not been fully elucidated. For pilots and astronauts, physical training is a basic method of enhancing their fitness and improving their tolerance to effects of special environmental factors. But the...