Preliminary results of medical investigations during manned flights of the Salyut 4 orbital station.

In 1975 the Soviet Union performed two manned flights on board the orbital station Salyut 4. The first mission of 30 days was flown by A. A. Gubarev (Commander) and G. M. Grechko (Flight Engineer) and the second mission of 63 days by P.I. Klimuk (Commander) and V.I. Sevastyanov (Flight Engineer). The present paper gives preliminary data on the general health and cardiovascular investigations of the crew members during and after flight. The clinical and physiological examinations of the cosmonauts showed that the work-rest cycles and counter-measures used helped to maintain their good health and high performance in flight, to alleviate adverse reactions and to facilitate readaptation post-flight. Medical results of the post-flight investigations revealed no changes that may detract from further increasing the duration of manned space missions.

Results of medical investigations carried out on board the Salyut orbital stations.

The purpose of the medical investigations carried out in flights of the Soviet orbital station Salyut were: to further studies and clarification of the phenomenology and mechanisms of changes in the main functions of the human body during prolonged weightlessness; to accumulate additional data on human responses at an early stage of adaptation to weightlessness; to assess the effectiveness of countermeasures against adverse effects of weightlessness during and after flight. The orbital station was equipped with a set of countermeasuring devices: a trainer for physical exercises (a treadmill), gravity simulation suit for long wear, bicycle ergometer, anti-G suit to be worn immediately post-flight, drugs, etc. The system of medical control included daily recordings of electrocardiography and respiration and regular physical examinations using provocative tests (physical exercises of a known force, lower-body negative pressure). Specific biomedical investigations were performed before, during and after flight. As in previous flights, the atmosphere in the habitable modules was similar to that on the earth. Food supply met the requirements for basic nutrients and satisfied individual preferences of the crew members. In addition to the time required to fulfil the flight programme, the work-rest schedule allowed the cosmonauts 8 hours sleep, four meals, 2.5 hours physical training and personal time. The biomedical investigations carried out during and after flight furnished information towards a better understanding of human responses to the effects of space flight factors and the mechanisms underlying their development.