biologia: Physiological effects in space

Evidence: 100 • authority: 72

Even before humans began to venture into space, serious and reasonable concerns were expressed about exposure of humans to the microgravity of space due to the potential systemic effects on terrestrially evolved life-forms adapted to Earth gravity. Unloading of skeletal muscle, both on Earth via bed-rest experiments and during spaceflight, result in remodeling of muscle (atrophic response). As a result, decrements occur in skeletal-muscle strength, fatigue resistance, motor performance, and connective-tissue integrity. In addition, weightlessness causes cardiopulmonary and vascular changes, including a significant decrease in red blood cell mass, that affect skeletal muscle function. Normal…

Evidence: 64 • authority: 90

The effects of spaceflight microgravity on the musculoskeletal system of humans and animals, with an emphasis on exercise as a countermeasure: a systematic scoping review. The purpose of this systematic review is twofold: 1) to identify, evaluate, and synthesize the heretofore disparate scientific literatures regarding the effects of direct exposure to microgravity on the musculoskeletal system, taking into account for the first time both bone and muscle systems of both humans and animals; and 2) to investigate the efficacy and limitations of exercise countermeasures on the musculoskeletal system under microgravity in humans.The Framework for Scoping Studies (Arksey and O'Malley 2005) and t…

Evidence: 64 • authority: 90

Revisiting the Role of Exercise Countermeasure on the Regulation of Energy Balance During Space Flight. A body mass loss has been consistently observed in astronauts. This loss is of medical concern since energy deficit can exacerbate some of the deleterious physiological changes observed during space flight including cardiovascular deconditioning, bone density, muscle mass and strength losses, impaired exercise capacity, and immune deficiency among others. These may jeopardize crew health and performance, a healthy return to Earth and mission’s overall success. In the context of planning for planetary exploration, achieving energy balance during long term space flights becomes a research a…

Evidence: 57 • authority: 90

Exercise in space: human skeletal muscle after 6 months aboard the International Space Station. The aim of this investigation was to document the exercise program used by crewmembers (n = 9; 45 +/- 2 yr) while aboard the International Space Station (ISS) for 6 mo and examine its effectiveness for preserving calf muscle characteristics. Before and after spaceflight, we assessed calf muscle volume (MRI), static and dynamic calf muscle performance, and muscle fiber types (gastrocnemius and soleus). While on the ISS, crewmembers had access to a running treadmill, cycle ergometer, and resistance exercise device. The exercise regimen varied among the crewmembers with aerobic exercise performed ap…

Evidence: 51 • authority: 88

Exercise Countermeasures: Optimizing Human Performance for Space. <div class="htmlview paragraph">Prolonged microgravity exposures induce physiological changes that result in deconditioning of the cardiovascular, neurosensory, and musculoskeletal systems. These changes may have important implications as flight durations lengthen and specific mission tasks place higher demands on crewmembers (e.g., space station construction, extravehicular activity contingencies, emergency egress). Historically, the United States and Russia have incorporated a variety of countermeasures in an effort to maintain human health and performance of crewmembers before, during, and after space flight. The NASA coun…

Evidence: 51 • authority: 90

Mitigating disuse‐induced skeletal muscle atrophy in ageing: Resistance exercise as a critical countermeasure. The gradual deterioration of physiological systems with ageing makes it difficult to maintain skeletal muscle mass (sarcopenia), at least partly due to the presence of 'anabolic resistance', resulting in muscle loss. Sarcopenia can be transiently but markedly accelerated through periods of muscle disuse-induced (i.e., unloading) atrophy due to reduced physical activity, sickness, immobilisation or hospitalisation. Periods of disuse are detrimental to older adults' overall quality of life and substantially increase their risk of falls, physical and social dependence, and early morta…

Evidence: 44 • authority: 80

Potential exercise countermeasures to attenuate skeletal muscle deterioration in space

Evidence: 44 • authority: 92

Physiological Changes in the Cardiovascular System During Space Flight - Current Countermeasures and Future Vision.. Background With the recent acceleration of manned space exploration, health care in space has become an important issue. Cardiovascular problems, mainly caused by the microgravity environment in space, include decreased red blood cell volume, myocardial atrophy and aerobic capacity, and reduced orthostatic tolerance after return. However, complete physiological countermeasures have not been established and more research is needed. Methods and results A search on PubMed was conducted for English-language articles on cardiovascular changes in space and their countermeasures and…

Evidence: 44 • authority: 90

The Impact of Step Reduction on Muscle Health in Aging: Protein and Exercise as Countermeasures. Declines in strength and muscle function with age-sarcopenia-contribute to a variety of negative outcomes including an increased risk of: falls, fractures, hospitalization, and reduced mobility in older persons. Population-based estimates of the loss of muscle after age 60 show a loss of ~1% per year while strength loss is more rapid at ~3% per year. These rates are not, however, linear as periodic bouts of reduced physical activity and muscle disuse transiently accelerate loss of muscle and declines in muscle strength and power. Episodic complete muscle disuse can be due to sickness-related bed…

Evidence: 44 • authority: 72

The International Space Station is a platform for scientific research that requires one or more of the unusual conditions present in low Earth orbit (for example microgravity, (cosmic) -radiation and extreme temperatures). The primary fields of research include human research, space medicine, life sciences, physical sciences, astronomy and meteorology. The 2005 NASA Authorization Act designated the American segment of the International Space Station as a national laboratory with the goal of increasing the use of the ISS by other federal agencies and the private sector. Released research has been presented and maid available through the ISS National Laboratory, summarized annually by NASA. R…

Evidence: 38 • authority: 80

Human skeletal muscle responses to spaceflight and possible countermeasures

Evidence: 38 • authority: 80

Effectiveness of Exercise Countermeasures for Protecting Muscle on the International Space Station (ISS)