Preliminary results of medical research on board the "Mir" orbital complex during its second main mission.

In 1987 the USSR orbital complex "Mir" accomplished its space mission, crewed by Yu.V. Romanenko (326 days), and A.I. Laveykin (about 176 days), who was replaced on the orbit (in consequence of some cardiac function peculiarities revealed in exercise conditions) by A.P. Aleksandrov (about 160 days). During the flight, extravehicular activity in the open space was carried out three times, and conjoint programmes were conducted, over a period of seven days, with an international Soviet-Syrian crew. The most important, fundamental result of the medical studies carried out in this flight seems to be the noted fact that Yu.V. Romanenko's 326 days in-flight (which means 3 months in excess to the results obtained hitherto) and his activity was not accompanied by developing any quantitatively new functional shifts, when compared to other long-term flights. Besides that, the cosmonaut maintained his functional endurance and work capacity on satisfactory levels. These results are in apparent relation with the rationally composed crew complement, the contribution the ground services responsible for the work-rest regimen and the whole life activity on board the station, as well as with the systematic and sufficiently extensive use of preventive measures. The general feeling and work capacity of the other crew members were also good throughout the flight. However, the reactions observed in each cosmonaut showed their individual characteristics, which are discussed in the paper.