During the 140-day flight of the orbital station Salyut-6 two primary crewmembers performed 5 exercise tests on a bicycle ergometer at a load of 750 kgm/min for 5 min. During tests heart rate, and ...before and after tests arterial pressure, left ventricular chronograms and cardiac output (rheographically) were recorded. In comparison to the preflight tests, the flight tests were characterized by less expressed changes in phasic parameters, moderate increase in cardiac output and, occasionally, insufficient decrease in peripheral resistance. These changes can be attributed to the weightlessness-associated deficiency of the circulating blood volume.
During the 140-day flight of the Salyut-6 station cardiovascular examinations were carried out at rest. They showed blood redistribution and hyervolemia of the upper body. They also demonstrated ...increases in the circulating blood volume and pulse blood filling of cerebral vessels, development of the phase preload syndrome and simultaneous decrease in blood filing of leg vessels. These changes varied phasically in the course of flight. Weightlessness of up to 140 days did not cause any pathologies in the cardiovascular system.
