Countermeasures in longterm spaceflights. Russian experience

The system of countermeasures was developed in Russia, that included as primary components: physical methods aimed to maintain the distribution of fluids at levels close to those experienced on Earth; physical exercises and loading suits aimed to load the musculoskeletal and the cardiovascular systems; measures that prevent the loss of fluids, mainly, water-salt additives which aid to maintain orthostatic tolerance and endurance to gravitational overloads during the return to Earth; well-balanced diet and medications directed to correct possible negative reactions of the body to weightlessness. The system tested in flights with more than 80 participants of primary missions who worked on Russian space stations from 16 to 438 days, demonstrated the capability to maintain cosmonauts health and performance during flight and to prevent or significantly reduce the negative consequences of long-duration stays in weightlessness after its conclusion. To control the performance of physical exercises periodic monthly sessions of recording crew performance on the training devices were provided. The effectiveness of the training mode performed by crew members was also assessed according to the parameters of the treadmill test with gradually increasing locomotor loads. Testing the state of the cosmonauts´ physiological functions and work capacity level after completion of the flight, opened the opportunity to evaluate the effectiveness of the system when it was utilized fully or in reduced modes, and also when it was used in one or another modification proposed by crew members.