[Results of a hemodynamic and cardiac cycle phase structure study in a functional test with measured physical load on a 140-day flight in the Saliut-6 station].

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.