Astronaut physiology
Definition
Space physiology is the study of the effects of space travel on the human body. It is a subfield of space medicine that focuses on the physiological changes that occur in the body during spaceflight.[1]
Effects of Microgravity on the Body
Microgravity, or weightlessness, has a profound impact on the human body. In space, the body does not have to work as hard to maintain posture and movement, which can lead to a range of effects, including:
- Muscle atrophy: Prolonged exposure to microgravity can cause muscles to weaken and shrink, particularly in the lower body.[2]
- Bone loss: In microgravity, the body does not have to work as hard to maintain bone density, leading to a loss of bone mass, particularly in the weight-bearing bones of the lower body.
- Fluid shift: In microgravity, fluids in the body shift towards the upper body, leading to puffy faces, congested sinuses, and other issues.
- Cardiovascular changes: Microgravity can cause changes in blood pressure, cardiac output, and vascular resistance.[3]
Other Effects of Space Travel on the Body
In addition to the effects of microgravity, space travel can also cause a range of other physiological changes, including:
- Radiation exposure: Space travelers are exposed to higher levels of cosmic radiation, which can increase the risk of cancer and other health problems.[4]
- Sleep disturbances: The unusual environment of space can disrupt sleep patterns, leading to fatigue and other issues.
- Immune system suppression: Space travel can weaken the immune system, making astronauts more susceptible to illness.
- Vision impairment: Prolonged exposure to microgravity can cause changes in the shape of the eye, leading to vision problems.
Adaptation to Space Travel
Astronauts undergo a range of physiological changes as they adapt to space travel. These changes can include:
- Orthostatic intolerance: Astronauts may experience dizziness and lightheadedness when standing up after prolonged periods in microgravity.
- Space adaptation syndrome: Astronauts may experience a range of symptoms, including nausea, vomiting, and disorientation, as they adapt to the microgravity environment.
Countermeasures
To mitigate the effects of space travel on the body, astronauts use a range of countermeasures, including:
- Exercise: Regular exercise can help maintain muscle mass and bone density.
- Resistance bands: Resistance bands can be used to provide resistance and help maintain muscle strength.
- Lower body negative pressure: Lower body negative pressure (LBNP) devices can be used to simulate the effects of gravity on the lower body.
- Sleep schedules: Astronauts follow strict sleep schedules to help regulate their sleep patterns.
See Also
- Space medicine
- Space adaptation syndrome
- Orthostatic intolerance
- Radiation exposure
- Space adaptation syndrome
External Links
- NASA's Human Research Program
- European Space Agency's Human Physiology in Space
- National Space Biomedical Research Institute's Space Physiology
References
- ↑ Barratt MR, Pool SL (eds). (2008) Principles of Clinical Medicine for Space Flight. Springer, New York.
- ↑ Convertino VA, Sandler H. (1995) Effects of microgravity on the musculoskeletal system. In: Fregly MJ, Blatteis CM (eds) Handbook of Physiology: Environmental Physiology.
- ↑ Smith JJ, Porth CM. (1991) Posture and the circulation: the physiology and pathophysiology of orthostasis. Journal of Clinical Pharmacology, 31(5): 444-451.
- ↑ Durante M, Cucinotta FA. (2008) Heavy ion carcinogenesis and human space exploration. Nature Reviews Cancer, 8(6): 465-472.