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Michel, E. L.

Publications and source records attributed to Michel, E. L..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Economy of middeck payloads

The utilization of the middeck, designed as the crew quarters, for experiments is examined. The dimensions of the middeck's standard lockers, double lockers, adapter plates, and the galley, which are applicable for experiments, are described. The utilities available for middeck payloads include ac and dc electrical power supply, active and passive cooling, vacuum/vent line connections, and data handling, and four basic payload configurations are possible. The development of a middeck accommodations rack to make payload space more flexible and to enable an optimum number and variety of experiments to be flown is proposed. Diagrams of the orbiter's middeck and experimental designs are provided.

Michel, E. L.↗
NASA NTRS1977

Results of Skylab medical experiment M171-metabolic activity

The primary objective of the experiment was to determine whether man's metabolic effectiveness while performing mechanical work was progressively altered by exposure to the space environment. The secondary objective was to evaluate the M171 bicycle ergometer as an in-flight crew personal exerciser. This manuscript is the report of the third (Skylab 4) manned mission and a summary of what was learned from all three Skylab manned missions about the physiological response to exercise during and after periods of 28 days, 59 days, and 84 days of weightlessness, respectively.

Michel, E. L.↗
NASA NTRS1977

Pulmonary function evaluation during and following Skylab space flights

Cardiac output measurements were made in the laboratory during preflight and postflight exercise tests. Due to the magnitude of decreases in cardiac output following the first and second manned Skylab missions and because the method used is based upon normal pulmonary function, it was decided to perform more thorough pulmonary function screening in conjunction with the final and longest duration Skylab mission. This paper summarized pulmonary function data obtained during all three Skylab missions.

Sawin, C. F.↗
NASA NTRS1976

Exercise cardiac output following Skylab missions - The second manned Skylab mission

Cardiac output was measured during preflight and postflight exercise-stress tests on the Skylab astronauts. In the postflight tests immediately following the 28-, 59-, and 84-d earth orbital missions, the astronauts exhibited an approximate 30% decrease in cardiac output coupled with an approximate 50% decrease in cardiac stroke volume during exercise. These changes were accompanied by elevated heart rates and significant increases in total systemic peripheral vascular resistance. Mean arterial pressure was unchanged. All parameters returned to normal preflight values within 30 d of the end of the orbital period. Duration of the zero-G exposure did not appear to influence either the magnitude of the hemodynamic changes or the time-course of their return to normal. These results are discussed in relation to other cardiovascular findings and possible mechanisms responsible for the observations are outlined.

Buderer, M. C.↗
NASA NTRS1976

Pulmonary function evaluation during the Skylab and Apollo-Soyuz missions

Previous experience during Apollo postflight exercise testing indicated no major changes in pulmonary function. Pulmonary function has been studied in detail following exposure to hypoxic and hyperoxic normal gravity environments, but no previous study has reported on men exposed to an environment that was both normoxic at 258 torr total pressure and at null gravity as encountered in Skylab. Forced vital capacity (FVC) was measured during the preflight and postflight periods of the Skylab 2 mission. Inflight measurements of vital capacity (VC) were obtained during the last 2 weeks of the second manned mission (Skylab 3). More detailed pulmonary function screening was accomplished during the Skylab 4 mission. The primary measurements made during Skylab 4 testing included residual volume determination (RV), closing volume (CV), VC, FVC and its derivatives. In addition, VC was measured in flight at regular intervals during the Skylab 4 mission. Vital capacity was decreased slightly (-10%) in flight in all Skylab 4 crewmen. No major preflight-to-postflight changes were observed. The Apollo-Soyuz Test Project (ASTP) crewmen were studied using equipment and procedures similar to those employed during Skylab 4. Postflight evaluation of the ASTP crewmen was complicated by their inadvertent exposure to nitrogen tetroxide gas fumes upon reentry.

Sawin, C. F.↗
NASA NTRS1976

Biomedical results of the Skylab Program

Skylab, the fourth in a logical sequence of USA manned space flight projects following Mercury, Gemini and Apollo, presented life scientists with their first opportunity for an in-depth study of man's response to the space environment. Extensive medical investigations were undertaken to increase our understanding of man's adaptation to the space environment and his readaptation to gravity upon return to earth. The flight durations of the three Skylab missions were progressively increased from 28 days to 59 days and, finally, 84 days. The results of these investigations of the various body systems clearly denonstrated that man can adapt to zero gravity and perform useful work during long-duration space flight. However, definite changes (some unexpected) in the vestibular, cardiovascular, musculo-skeletal, renal and electrolyte areas were documented. The most significant were: the occurrence of space motion sickness early in the missions; diminished orthostatic tolerance, both in-flight and post-flight; moderate losses of calcium, phosphorus and nitrogen; and decreased tolerance for exercise post-flight. The mechanisms responsible for these physiological responses must be understood and, if necessary, effective countermeasures developed before man can endure unlimited exposure to space flight.

Michel, E. L.↗
NASA NTRS1975

Physiological response to exercise after space flight - Apollo 14 through Apollo 17

Submaximal exercise stress tests were conducted preflight and postflight on the Apollo 14-17 crewmen. A bicycle ergometer was utilized to evoke target heart rates up to 160 beats/min while respiratory gas exchange, blood pressure, and cardiac output were measured. Three preflight tests were conducted during the month prior to flight to establish baseline values for postflight comparisons. Tachycardia was evidenced at rest and during exercise immediately postflight. This transitory tachycardia compensated for reduced stroke volume. Systolic blood pressure was reduced during exercise stress, but no consistent changes were observed in diastolic blood pressure. With the exception of the Apollo 15 crewmen, all crewmen had returned to preflight response levels by the day following recovery. No changes were observed in mechanical or respiratory efficiency immediately postflight.

Rummel, J. A.↗
NASA NTRS1975

Instrumented personal exercise during long-duration space flights

The present work reports the results of instrumented personal exercise performed in flight by Skylab 3 and 4 crewmen. Inflight cycle ergometer data provide conclusive evidence that man can perform earthbound equivalent maximum levels of physical work while in the zero-G environment. Moreover, SL4 crewmen were able to improve their physical condition during 84 days of space flight relative to launch condition, due to rigorous personal exercise regimens. Biological data measured included oxygen consumption, CO2 production, minute volume, and heart rate.

Sawin, C. F.↗
NASA NTRS1975

Skylab experiment M-171 'Metabolic Activity' - Results of the first manned mission

The experiment was performed to ascertain whether man's ability to perform mechanical work would be altered as a result of exposure to the weightless environment. Skylab II crewmen were exercised on a bicycle ergometer at loads approximating 25%, 50%, and 75% of their maximum oxygen uptake while their physiological responses were monitored. The results of these tests indicate that the crewmen had no significant decrement in their response to exercise during their exposure to zero gravity. Immediately postflight, however, all crewmen demonstrated an inability to perform the programmed exercise with the same metabolic effectiveness as they did both preflight and inflight. The most significant changes were elevated heart rates for the same work load and oxygen consumption (decreased oxygen pulse), decreased stroke volume, and decreased cardiac output at the same oxygen consumption level. It is apparent that the changes occurred inflight, but did not manifest themselves until the crewmen attempted to readapt to the 1-G environment.

Michel, E. L.↗
NASA NTRS1975

The medical story

The paper discusses the medical program of the Skylab missions. The major medical systems discussed include the food system, the waste-management system, the personal-hygiene system, and the inflight medical support system. The life-sciences experiments conducted on Skylab are reviewed. These dealt with the cardiovascular system, mineral balance and bioassay of fluids, sleep, blood, metabolic activity, vestibular function, and time and motion studies. The medical operations were accomplished with only minor problems.

Johnston, R. S.↗
NASA NTRS1974

Results of Skylab medical experiment M171: Metabolic activity

The experiment was conducted to establish whether man's ability to perform mechanical work would be progressively altered as a result of exposure to the weightless environment of space flight. The Skylab crewmen exercised on a bicycle ergometer at workloads approximating 25, 50, and 75 percent of their maximum aerobic capacity. The physiological parameters monitored were respiratory gas exchange, blood pressure, and vectorcardiogram/heart rate. The results of these tests indicate that the crewmen had no significant decrement in their responses to exercise during their exposure to zero gravity. The results of the third manned Skylab mission (Skylab 4) are presented and a comparison is made of the overall results obtained from the three successively longer Skylab manned missions. The Skylab 4 crewmembers' 84-day in-flight responses to exercise were no worse and were probably better than the responses of the crewmen on the first two Skylab missions. Indications that exercise was an important contributing factor in maintaining this response are discussed.

Michel, E. L.↗
NASA NTRS1974

Pulmonary function evaluation during and following Skylab space flights

Previous experience during the Apollo postflight exercise testing indicated no major changes in pulmonary function. Although pulmonary function has been studied in detail following exposure to hypoxic and hyperoxic environments, few studies have dealt with normoxic environments at reduced total pressure as encountered during the Skylab missions. Forced vital capacity was measured during the preflight and postflight periods of the Skylab 2 mission. Initial in-flight measurements of vital capacity were obtained during the last two weeks of the second manned mission (Skylab 3). Comprehensive pulmonary function screening was accomplished during the Skylab 4 mission. The primary measurements made during Skylab 4 testing included residual volume determination, closing volume, vital capacity, and forced vital capacity and its derivatives. In addition, comprehensive in-flight vital capacity measurements were made during the Skylab 4 mission. Vital capacity was decreased slightly during flight in all Skylab 4 crewmen. No major preflight to postflight changes were observed in the other parameters.

Sawin, C. F.↗
NASA NTRS1974

Automated measurement of respiratory gas exchange by an inert gas dilution technique

A respiratory gas analyzer (RGA) has been developed wherein a mass spectrometer is the sole transducer required for measurement of respiratory gas exchange. The mass spectrometer maintains all signals in absolute phase relationships, precluding the need to synchronize flow and gas composition as required in other systems. The RGA system was evaluated by comparison with the Douglas bag technique. The RGA system established the feasibility of the inert gas dilution method for measuring breath-by-breath respiratory gas exchange. This breath-by-breath analytical capability permits detailed study of transient respiratory responses to exercise.

Sawin, C. F.↗
NASA NTRS1974

The medical story

An overview of the Skylab medical program is given. All medical subsystems provided in the orbital workshop functioned satisfactorily. Major systems included the food system, the waste management system, and provisions per personal hygiene. A series of lockers in the wardroom was used to stow the inflight medical support system. Cardiovascular counter pressure garments were launched in the orbital workshop for all three crews. Life services experiments were carried out. Two experiments were conducted in the Skylab missions to study the performance of the cardiovascular system during weightless flight and return to earth and the one g environment. A series of experiments was conducted to study mineral balance and the bioassay of body fluids.

Johnston, R. S.↗
NASA NTRS1973

Metabolic activity, experiment M171

The Skylab metabolic activity experiment determines if man's metabolic effectiveness in doing mechanical work is progressively altered by a simulated Skylab environment, including environmental factors such as slightly increased pCO2. This test identified several hardware/procedural anomalies. The most important of these were: (1) the metabolic analyzer measured carbon dioxide production and expired water too high; (2) the ergometer load module failed under continuous high workload conditions; (3) a higher than desirable number of erroneous blood pressure measurements were recorded; (4) vital capacity measurements were unreliable; and (5) anticipated crew personal exercise needs to be more structured.

Michel, E. L.↗
NASA NTRS1973

Physiological response to exercise after space flight - Apollo 7 to Apollo 11.

Exercise response tests were conducted preflight and postflight on Apollo missions 7 to 11. The primary objective of these tests was to detect any changes in the cardiopulmonary response to exercise that were associated with the space flight environment and that could have limited lunar surface activities. A heart-rate-controlled bicycle ergometer was used to produce three heart rate stress levels: 120 beats per minute for 6 minutes; 140 beats per minute for 3 minutes and 160 beats per minute per 3 minutes. Work load, blood pressure and respiratory gas exchange were measured during each stress level. Significant decreases were observed immediately postflight in the following dependent variables at a heart rate of 160 beats per minute: work load, oxygen consumption, systolic blood pressure, and diastolic blood pressure. No changes occurred in work efficiency at 100 watts or the ventilatory equivalent for oxygen at 2.0 liters per minute.

Rummel, J. A.↗