[Work capacity evaluation and orthostatic tolerance in experiments with long-term isolation]. / Fizicheskaia rabotosposobnost' i ortostaticheskaia ustoichivost' v éksperimentakh s dlitel'noi izoliatsiei.

Orthostatic tolerance (OT) and physical performance were tested against the ground simulation of several spaceflight factors. Before and after prolonged isolation and confinement three human subjects were tested by tilting, LBNP, and graded incremental aerobic exercise in the sitting position. Results suggested good OT in all the subjects. However, the pattern of orthostatic reaction was modified depending on the initial functional state of each subject. This was especially distinct in subjects 002 and 003 whose OT was slightly reduced by the experimental conditions. Orthostatic reactions in subject 004 showed greater stability in the baseline data collection period and was not much affected by isolation and confinement. HR variations at rest carried an individual character. On the whole, HR tended downward, particularly in 002. Indices of AP and, to a higher degree, its systolic constituent wandered outside the region of baseline values and even the norm limits in 002 and 004. Maximum variations were documented at the end of the second (003 and 004) and the third (002) months in experiment. ECG parameters in all the operators displayed different patterns of the norm. Diffusive repolarization, especially in the left chest leads, was noted to decline in the experiment. Tolerance of LBNP was qualified as good. Meanwhile, subject 003 developed symptoms of strained functioning of compensatory/adaptive mechanisms responsible for the OT maintenance. Repeated testing by LBNP was found to raise HR. Hence, prolonged simulation of space flight causes some reduction of orthostatic and LBNP tolerance, and degradation of physical performance.

[The cardiovascular system function of the cosmonauts of the 6th prime expedition on the Mir station]. / Funktsional'noe sostoianie serdechno-sosudistoi sistemy kosmonavtov shestoi osnovnoi ékspeditsii na stantsii "Mir".

Medical results of inflight cardiovascular measurements made in the 6th prime crew at rest and during provocative graded bicycle exercises and LBNP tests are presented. The methods of electrocardiography, tetrapolar rheography, kinetocardiography, arteriovenous pulsography and tacho-oscillography have been used to examine the cosmonauts. Together with regular cardiovascular changes typical of microgravity effect the individual peculiarities of developing the control mechanisms are noted. Thus in one of the cosmonauts a number of symptoms responsible for a decreased venous return. As a whole the functional state of the cardiovascular system on all flight stages was characterized by a sufficiently high physiological level.

[Anthropometric studies of crew members of Salyut-6 and Salyut-7]. / Antropometricheskie issledovaniia osnovnykh ékipazhei na orbital'nykh stantsiiakh "Salyut-6" i "Salyut-7".

The paper presents body mass and leg volume measurements of 21 prime crewmembers of Salyut-6 and Salyut-7 flights. It was found that body mass variations were different in sign. In most crewmembers body mass decreased by 1.2-2.0 to 6.0 kg. In some crewmembers this parameter increased by 1.0 to 4.5 kg during the entire flight or at certain flight stages. This observation confirms the concept that metabolism produces an important effect on body mass variations. It also points out that the space diets used are adequate to metabolic requirements. Leg volume of all cosmonauts decreased in the following manner: the decrease was the greatest during the first flight day, slightly less during the first flight month and still less during the subsequent 2 or 3 months of flight. Exercises that were performed at a larger workload, especially during the second half of flight, seemed to help stabilize or occasionally increase leg volume.

Medical investigations results obtained in 125-day flight on "Salyut-7" and "Mir" orbital stations.

In 1986 in USSR medical investigations were continued in 125-day flight on "Salyut-7" and "Soyuz-T-15" orbital stations and on "Mir" basic block. Medical program consisted of medical control during active parts of flight and works in open space, profound medical examinations in rest and in function tests, metabolism and its regulation analysis, hygienic estimation of environment, estimation of prophylactic methods to prevent unfavourable influence of weightlessness on human organism. Cosmonauts felt well in all parts of flight on the dates of radio exchange, TV-seances, self- and each other control. Profound medical investigations discovered several individual changes in parametres of every cosmonaut's blood system. This charactaral changes appeared not in rest only, but with the influence of loading test and depended on initial hemodynamic status before the test.

[Results of medical research carried out in 1985 on prolonged space flights]. / Rezul'taty meditsinskikh issledovanii, vypolnennykh v 1986 g. v dlitel'nykh kosmicheskikh poletakh.

This paper presents medical results obtained during the fourth expedition of five cosmonauts onboard orbital complexes Salyut-7--Soyuz-T-13 and Salyut-7--Soyuz-T-14. The cardiovascular system was examined using 36 resting and provocative tests. They were performed by means of electrocardiography, tetrapolar rheography, arteriovenous pulsography and tachooscillography. In addition, body mass and leg volume were measured. The above parameters showed typical variations as well as individual changes related to the preflight circulation level and environmental effects. The use of modified regimens of provocative tests demonstrated their applicability to the assessment of the cardiovascular function in space flight.

[Effect of dihydroergotamine on blood circulation in man in conditions of orthostasis]. / Vliianie digidroérgotamina na gemotsirkuliatsiiu cheloveka v usloviiakh ortostaza.

The physiological effects of zero-g were simulated by 6-hour antiorthostatic hypokinesia at -15 degrees, using eight healthy volunteers. They took part in two experimental runs at a 2 week interval. During the first study the test subjects received a placebo and during the second study they got 6 mg dihydroergotamine methane sulfonate per os. Radiometric examinations of the whole body and its compartments (head, chest, abdomen, legs) showed that the drug increased blood pooling in the upper body and decreased it in the lower body at every position of the long axis of the body relative to the gravity vector.

[Effects of sidnocarb on hemodynamics and blood redistribution during functional tests after 6-hour antiorthostatic hypokinesis]. / Vliianie sidnokarba na gemodinamiku i pereraspredelenie krovi pri funktsional'nykh probakh posle 6-chasovoi antiortostaticheskoi gipokinezii.

Man's orthostatic tolerance and physical work capacity declined in response to 6-hour head-down tilt at -15 degrees. During tilt tests heart rate increased, blood pressure fell, and blood pooling in the upper body decreased. During exercise tests the circulating blood volume, total amount of the work performed, and consumed oxygen decreased. Sydnocarb given at a dose of 25 mg during head-down tilt did not influence the circulating blood volume and oxygen consumption. All other parameters varied approaching the pretest values.

[Effect of sidnocarb during 7-day water immersion on the cardiorespiratory system under physical load]. / Vliianie sidnokarba v usloviiakh 7-sutochno vodnoi immersii na sostoianie kardiorespiratornoi sistemy pri fizicheskoi nagruzke.

To study physiological effects of weightlessness, 12 male volunteers, aged 25-33, were exposed to 7-day water immersion. The test subjects were divided into two groups of 6 in each: the first group subjects were given a new Soviet stimulant sydnocarb (3-(beta-phenylisopropyl) -N-phenyl carbamoyl sydnonimine) and the second group subjects were given a placebo, using the double-blind method. To evaluate the cardiorespiratory function, the test subjects exercised on a bicycle ergometer before and after water immersion. During exercises ECG, heart rate, minute respiration volume, oxygen consumption, carbon dioxide production, cardiac output, oxygen pulse were recorded. The test subjects on the placebo showed a significant decrease of oxygen consumption at at maximum workload. Those who were given sydnocarb maintained normal oxygen consumption during bicycle ergometry. The drug increased the workload per kg body weight, maintained physical work capacity, and improved the cardiovascular function after immersion.

[Effect of isoptin on the central and peripheral hemodynamics in hypokinesia in healthy persons]. / Vliianie izoptina na tsental'nuiu i perifericheskuiu gemodinamiku v usloviiakh gipokinezii u zdorovykh liudei.

Central and peripheral hemodynamics was studied by the radioisotope method employing 131I-labelled albumin, the blood flow in the muscles was investigated (using 133Xe) and the longitudinal rheovasogram of the leg and forearm recorded in 10 healthy male volunteers before, during, and after 45-day antiorthostatic hypokinesia. Five of the examines received isoptin, while the remaining 5 formed the control group. Due to the effect of hypokinesia a tendency towards a a decrease in the circulation volume, a reduced stroke index, an increase in the central venous pressure and peripheral resistance, and a decrease in the muscular blood flow were observed. With the prescription of isoptin the changes in the cardiac index and peripheral resistance were corrected, but there was no esstential effect on the level of the venous pressure and the muscular blood flow.