[Characteristics of cosmonauts' metabolism after extended missions on the international space station].

In eight Russian members of the ISS crews 1 to 5 enzymes and some other metabolites were analyzed in blood in the pre- launch period, on the landing day, and on days 6-8 and 14-19 of recovery. Deviations in the biochemical parameters were typically within the physiological norm without clinical implications. Biochemical deviations on the landing day seemed to relate to metabolic shifts due to long-term microgravity and, on the other hand, were a reaction to acute gravitational stress on return to 1 g. Dynamics of a number of parameters was markedly different as compared with the data from cosmonauts who had made long missions to the Mir space station, but this can be attributed to different g-profiles during descent and blood sampling schedule. In two to three wks the parameters regained normal values suggesting that negative effects of readaptation to the Earth's gravity were fully remedied.