[Possibility to predict cosmonauts' orthostatic tolerance following short-and long-term space flights].

According to the analysis of the data of active and passive orthostatic tolerance (OST) testing before and after 67 short- (SSF) and 53 long-term (LSF) space flights OST declined in all the cosmonauts regardless of flight length. Active testing on R+1 after SSF (7 to 25 d) and LSF (49 to 438 d) attested OST loss by 33% and 48%, respectively. Full OST recovery following SSF and LSF was observed in a week and 1.5-2 months, respectively. A correlation was established (r = 0.81) between the post-flight OST loss and pre-flight baseline value. Depending on whether the pre-flight OST value was very good, good or satisfactory, its loss on R+1 after LSF can make up 20-30%, 30-50% and 55-65%, respectively. Consequently, data of preflight OST testing can be used for prediction of its decline post normal space flight.