Effect of lunar gravity on metabolic rates.
Simulated lunar gravity effects on human metabolic rates in full pressure suits during physical exercise
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Simulated lunar gravity effects on human metabolic rates in full pressure suits during physical exercise
Long term effects of physical exercise and conditioning in the prevention and treatment of coronary heart disease are studied. Some aspects of the problem are outlined and difficulties encountered in a group of middle aged business executives using a carefully prescribed, but non-regimented and loosely supervised conditioning program employing commonly used forms of exercise (bicycling and jogging), are described.
Classification of blood hyperlipemias by electrophoresis or ultracentrifugation according to density fraction is described and therapeutic measures for humans with hyperlipoproteinemia are outlined. The statistically significant relationship between high serum cholesterol levels and incidence of coronary disease prescribes restricted caloric intake or physical exercise to burn excess calories as preventive measures.
An analysis was made of retest and followup counselling effects on the reduction of hypercholesterolemia levels in NASA employees. Criteria used to measure such control include motivation, age of patient, personality of patient, job stress, and physical exercise.
Prophylactic measures directed toward preservation of health and maintenance of the performance ability of a man during prolonged space flight stress center on the selection of optimum work and rest cycles, physical exercises, the use of pharmacological agents, conditioning of the cardiovascular apparatus, etc. A specially selected set of hormone and pharmacological preparations is recommended to stimulate hemopoiesis.
Housekeeping, off-duty, and medical data concerning the appliances considered for the space station are presented. Appliance functions analyzed include: cleanup, collection, processing and storage of refuse; crew entertainment and physical exercise, and the autoclaves and ergometers.
The general preliminary measures for treating insomnia include moderate physical exercise several hours before bedtime, and the relaxation of complex mental activity before bedtime. A case history concerning a woman with marital troubles is offered as evidence that insomnia may be caused by deeply rooted psychological and situational problems. Another case history illustrates how prior pharmacological treatment may complicate the process of clinically evaluating an insomniac.
Experiments were conducted on twelve women aged 23-34 yr - a bed rest (BR) group of eight subjects and an ambulatory (AMB) group of four subjects - to determine the effect of bed rest on shifts in plasma volume, electrolytes, and erythrocyte volume during +Gz acceleration on a centrifuge. The BR group underwent the +Gz acceleration during a two-week ambulatory control period, after 15 days of a 17-day BR period, and on the third day of ambulatory recovery. The AMB group underwent the same experimental procedures, but continued their normal daily routine during the BR period without additional prescribed physical exercise. Major conclusions are that (1) the higher the mean control tolerance, the greater the tolerance decline after BR; (2) relative confinement and reduced activity contribute as much to reduction in tolerance as does the horizontal body position during BR; (3) BR deconditioning has no effect on the erythrocyte volume during +3.0 Gz; and (4) about one-half the loss in tolerance after BR can be attributed to plasma volume and electrolyte shifts.
Data collected in the Skylab program relating to physiological stresses is presented. Included are routine blood measures used in clinical medicine as research type endocrine analyses to investigate the metabolic/endocrine responses to weightlessness. The daily routine of physical exercise, coupled with appropriate dietary intake, sleep, work, and recreation periods were considered essential in maintaining the crew's health and well being.
Depending upon the dominant type of symptoms, seasickness is divided into three forms: nervous, gastro-intestinal, and cardiovascular. Various medications are recommended appropriate to these forms. The first goal is normalization of impaired system functions as well as metabolism and the electrolyte and acid-base condition of the organism. Dietary recommendations are made and specific suggestions on the use of physical exercise, including prophylatic vestibular training exercises.
In an attempt to develop guidelines for classification by degree of intensity of various kinds of physical work performed by women, the effects of different work loads on women as compared to men were studied under industrial and experimental conditions, including response of the cardiovascular and respiratory systems to specified physical exercises of increasing intensity. Physiological criteria for assessing female labor in terms of intensity are proposed.
An analysis of published data are presented as well as the results of experiments which show that the state of weightlessness and hypodynamia result in a reduced orthostatic and vestibular resistance, increased sensitivity to infections, decreased endurance of accelerations and physical exercises, and altered reactivity of the organism to drugs. Various consequences of weightlessness on the human body, especially weightlessness combined with other factors linked to long space flights are also considered.
The influence of hypokinesia on the oxygen consumption of rats, dog, and squirrels was investigated. Three periods of gaseous exchange were revealed in rats under conditions of a limited motor activity. During the first 10-15 days O2 consumption displayed a sharp elevation; on the 20th-30th day, it became stabilized at a higher level (in comparison with control) and it sharply rose again on the 40th-100th day. In dogs, hypokinesia produced a reduction of O2 consumption and then a tendency to its elevation was seen. A short period of physical exercises in squirrels after hypokinesia led to increased oxygen consumption at rest.
Blood microcirculation in the region of the scleral bulbar conjunctiva and the nail folds on the fingers and toes was studied in 18 practically healthy men during 182 day antiorthostatic hypokinesia and 30 day rehabilitation period. Marked changes in microcirculation in the sclera and feet and less evident changes on the hands was revealed. A complex of special prophylactic physical exercises had a distinctly favorable effect on circulation in the hands.
This bibliography of citations to the international literature covers aspects of altitude acclimatization. Included are articles concerning high altitude environments, hypoxia, heart function and hemodynamic responses, physical exercise, human tolerances and reactions, physiological responses, and oxygen consumption. This updated bibliography contains 164 citations, 35 of which are new entries to the previous edition.
Two male volunteers were kept hypokinetic in the immersion and physiological parameters were evaluated following the experiment. Prophylactic measures (g-forces, physical exercises, and supplementary salt and water) were applied daily. Caloric and equilibrium tests were utilized to evaluate the physiological responses. The functional changes observed after the 56 day immersion were found to be of a moderate type which normalized quite quickly.
The mechanisms of fluid loss in the human body while sweating due to physical exercise are discussed. Trained and untrained persons were examined and compared. Since sweat is hypotonous, a disruption in the hydrosalinic balance occurs; the consequences of this finding, also pertaining to the fluid and electrolytic substitution, are presented. Further explanations on the problem of dehydration refer to reactions of individual organ systems, to alterations in bodily capabilities as well as to questions relating to sex and age.
NASA's past, current, and planned research on muscle deterioration at zero gravity and development of countermeasures are reviewed; Soviet studies are discussed as well. A definition of muscle mass and strength regulation factors, and improved measurement methods of muscle atrophy are needed. Investigations of tissue growth factors and their receptors, endogenous and exogenous anabolic protein synthesis stimulation, and a potential neurotropic factor are among the projects in progress or planned. At present, vigorous physical exercise during spaceflight is recommended as the most effective countermeasure against skeletal muscle atrophy.