Space Flight and Astronaut’s Well-being
Introduction:
Maintaining optimal physical and mental health is essential for individuals to perform their duties effectively. Astronauts, however, are exposed to unusual environments, which can lead to physical or psychological problems due to the body's reaction to radiation and zero gravity (Williams et al., 2009). During space travel, astronauts encounter various surroundings, including the magnetosphere—the outer region of Earth's environment—which can physically impact the body due to radiation exposure (Dinatolo & Cohen, 2022).
Space travelers face numerous health issues in space due to environmental changes, radiation exposure, and the effects of gravity (Dinatolo & Cohen, 2022; Petersen et al., 2017). Gravity and environmental changes are vital for human health. The lack of gravity in space can disrupt the alignment and operation of blood vessels and valves, leading to circulation issues that affect all organs. It also hampers the body's ability to regulate water, causing dehydration, and weakens bones and muscles due to the pooling of blood in microgravity (Patel, 2020; HermanA Noordung, n.d.). Additionally, radiation exposure increases the likelihood of adverse health effects, particularly impacting the brain and central nervous system, potentially resulting in severe harm or even death (Dinatolo & Cohen, 2022).
https://youtu.be/t6tRfOPhjrI
The effects of gravity on astronauts:
The Earth's gravitational pull plays a crucial role in regulating the body's functions. It aids in maintaining muscle strength and ensuring proper blood flow by influencing the direction and function of various organs (Cavagna et al., 2000).
In space, astronauts experience weightlessness due to the absence of gravity, which Ranganathan & Bytes (2016) describe as a lack of gravitational force, resulting in potential health risks and disruptions to bodily functions. This absence of gravity can cause problems with blood circulation and heart function, potentially harming essential organs, redistributing bodily fluids, affecting muscles and bones, and altering nutrition, which can lead to motion sickness.
Impact of blood circulation on astronauts during space travel:
Gravity on Earth plays a crucial role in maintaining optimal blood circulation throughout the body, benefiting all organs. In zero gravity during space travel, fluid movement from blood vessels to surrounding tissues leads to a reduction in blood volume and affects the heart, causing facial swelling (Guzman, 2023; Rusanov et al., 2022). This can decrease blood pressure and impact heart output and circulation (Rusanov et al., 2022; Ranganathan & Bytes, 2016). Consequently, astronauts are closely monitored during their time in space to prevent any issues. Exercise is essential to maintain their cardiovascular fitness. Wearing specialized pants can help redistribute fluid and maintain blood volume (Guzman, 2023) in order to produce academic papers related to research.
Movement of bodily fluids:
In space, astronauts may experience a shift of body fluids from blood to tissues due to zero gravity, leading to decreased blood pressure, circulation, brain function, neurological function, and facial swelling (Guzman, 2023).
Andreev et al. (2018) noted that an increase in fluid in the skull can result in brain pressure and brain edema, while increased fluid in the heart can alter its shape, increase blood volume, and cause muscle atrophy (Guzman, 2023). NASA (2015) has acknowledged the challenges posed by zero gravity, which led to the implementation of exercise to regulate fluid volume and prevent health problems in astronauts. Assad & de Weck (2015) conducted a study on the medical supply model and astronaut health for long-duration human space flight. Their research showed that astronauts most commonly experience facial fullness (81%), with a slight decrease in heart rate (1.80%). This indicates that the primary issues involve facial swelling due to fluid redistribution.
Challenges with the musculoskeletal system and bone strength:
Zero gravity can negatively affect muscle and bone health within the musculoskeletal system. Reduced bone stress leads to a decrease in osteoblast cells, which are responsible for bone formation, and a loss of bone density (Ranganathan & Bytes, 2016). In a zero-gravity environment, bone cell formation is inefficient, causing calcium to build up in the blood and leading to issues such as kidney stones and fractures. Additionally, muscle mass and strength diminish, resulting in muscle atrophy and fiber loss due to a 15% reduction in muscle protein synthesis (Ranganathan & Bytes, 2016; Williams et al., 2009).
Williams et al. (2009) discovered that astronauts may experience a 20% reduction in calf muscle volume and a 50% decrease in muscle strength after extended space flights. They also recommended that exercising during space travel can help prevent muscle loss and improve muscle strength.
The influence of nutrition on motion sickness:
Astronauts require food and nutrition suitable for space travel and the absence of gravity. Motion sickness, characterized by stomach issues, nausea, and vomiting, is a common symptom experienced by astronauts in space (Dakkumadugula et al., 2023). This condition may result from a mismatch between visual and neurovestibular signals of movement, along with the complex interactions among the autonomic nervous system, gastrointestinal system, and cardiovascular system (Suri et al., 2020; Williams et al., 2009).
The health effects of zero gravity on an astronaut's body can disrupt their space missions. Therefore, astronauts undergo extensive training before their missions to address or minimize these issues. They are closely monitored both during their time in space and upon their return to Earth.
The effects of radiation on astronauts:
Radiation in space can be harmful to the human body, while the Earth's ozone layer protects all living organisms from external radiation. In space, radiation combined with microgravity can cause cognitive, structural, and behavioral issues in the brain by inducing fluid shifts and circulation problems, thus impacting brain structure and function (Dinatolo & Cohen, 2022). This combination can also increase intracranial pressure, leading to cognitive problems and neurovestibular system issues (Dinatolo & Cohen, 2022; Patel, 2020). Additionally, radiation can disrupt several body systems, including the cardiovascular system, potentially causing heart attacks, cataracts, digestive issues, weakened immune function, respiratory problems, and hormonal disorders. These challenges can be managed in space through thorough training in preventive methods and the use of specially designed protective suits to reduce radiation exposure (Patel, 2020).
The impact of extended space missions on mental health and psychological well-being:
Prolonged space missions can detrimentally affect astronauts' mental and
psychological health. The absence of gravity and exposure to radiation can
adversely impact the brain and nervous system, causing fluid shifts,
circulatory issues, and cognitive impairments due to increased intracranial
pressure, among other challenges encountered in space (Guzman, 2023; Dinatolo
& Cohen, 2022; Patel, 2020). Additionally, the various hazards of space
travel, including the isolation and distance from Earth, can lead to high
levels of stress and anxiety, significantly altering astronauts' behavior and
cognitive abilities (Patel, 2020). These cognitive abilities encompass
emotional regulation, mood stability, time management, and stress management
(Patel, 2020; Pagnini et al., 2023). Research by Yin et al. (2023) further
indicates that prolonged exposure to zero gravity can result in substantial
cognitive deficits, affecting task performance, emotional stability, mood, and
motor skills.
References:
Dinatolo, M. F., & Cohen, L. Y. (2022). Monitoring the Impact of Spaceflight on the Human Brain. Life (Basel, Switzerland), 12(7), 1060. https://doi.org/10.3390/life12071060
Williams,
D., Kuipers, A., Mukai, C. and Thirsk, R. (2009). Acclimation during space
flight: effects on human physiology. Canadian Medical Association Journal,
180(13), pp.1317–1323. doi:https://doi.org/10.1503/cmaj.090628.
HermanA
Noordung. (n.d.). Available at: https://history.nasa.gov/SP-4026.pdf.
Dakkumadugula, A., Pankaj, L., Alqahtani, A. S., Ullah, R., Ercisli, S., & Murugan, R. (2023). Space nutrition and the biochemical changes caused in Astronauts Health due to space flight: A review. Food Chemistry: X, 20, 100875. https://doi.org/10.1016/j.fochx.2023.100875
Petersen, N., Lambrecht, G., Scott, J., Hirsch, N., Stokes, M., & Mester, J. (2017). Postflight reconditioning for European Astronauts – A case report of recovery after six months in space. Musculoskeletal Science and Practice, 27, S23–S31. https://doi.org/10.1016/j.msksp.2016.12.010
Ranganathan,N.& Bytes, S. (2016) Cosmic Travels Inc.: The effect of zero gravity on the human body | SciBytes | Learn Science at Scitable. Scitable by nature education. Retrieved from: https://www.nature.com/scitable/blog/scibytes/cosmic_travels_inc_the_effect/
Cavagna, G., Willems, P., & Heglund, N. (2000). The role of gravity in human walking: pendular energy exchange, external work and optimal speed. The Journal of Physiology, 528(3), 657–668. https://doi.org/10.1111/j.1469-7793.2000.00657.x
Rusanov, V. B., Nosovsky, A. M., Pastushkova, L. H., Larina, I. M., & Orlov, O. I. (2022). The Order of Inclusion of Circulatory System Regulation Circuits in Adaptation Mechanisms during Simulation of Microgravity Effects via 5-Day Dry Immersion. Human Physiology, 48(6), 717–723. https://doi.org/10.1134/s0362119722600370
Guzman, A. (2023). Cardiovascular Health in Microgravity - NASA. NASA. https://www.nasa.gov/missions/station/cardiovascular-health-in-microgravity/
Andreev-Andrievskiy, A. A., Popova, A. S., Lagereva, E. A., & Vinogradova, O. L. (2018). Fluid shift vs. body size: changes of hematological parameters and body fluid volumes in hindlimb-unloaded mice, rats and rabbits. Journal of Experimental Biology. https://doi.org/10.1242/jeb.182832
NASA (2015). Study of human body fluid shifts aboard space station advances journey to Mars. https://phys.org/news/2015-07-human-body-fluid-shifts-aboard.html
Assad, A., & de Weck, O. L. (2015). Model of medical supply and astronaut health for long-duration human space flight. Acta Astronautica, 106, 47–62. https://doi.org/10.1016/j.actaastro.2014.10.009
osteoblast. (2023). In Merriam-Webster Dictionary. Retrived from: https://www.merriamwebster.com/dictionary/osteoblast