During missions to the International Space Station, astronauts’ bodies undergo a wide range of changes due to the absence of gravity – everything from vision to cardiovascular health to bone density is affected.
Although astronauts exercise and take supplements to lessen some of these effects, a better understanding of deconditioning in microgravity could allow doctors to design better treatments. This would not only be useful for astronauts; it could also improve treatment strategies for common health conditions here on Earth.
Stay dry in wet conditions
To do this, ESA’s SciSpacE team and a team of European scientists designed VIVALDI, which takes place at the Clinique Spatiale MEDES (Institut de Médecine et Physiologie Spatiales) in Toulouse, France – one of the only facilities in Europe that can host such studies. .
VIVALDI is an experience that focuses on what is called dry immersion – a ground analog of the effects of microgravity on the body. As the name suggests, dry immersion involves being submerged in water for long periods of time, while remaining dry. To do this, participants are dressed in waterproof fabric and lie in specially designed water baths. Their body is then submerged above the torso, with a fitted waterproof tarp keeping their arms and head out of the water.
During VIVALDI, participants spend five full days in this position. Meals are taken using a floating board and a neck pillow. For washroom breaks and other activities that require getting out of the water, participants are helped onto a cart, maintaining their relaxed position, and temporarily removed from the water by staff.
Submerging participants in this manner takes weight off the body, inducing microgravity-like alterations to the neurological, cardiovascular, and metabolic systems, to name a few. Fluids in the body change and physiological processes begin to resemble those seen in astronauts during spaceflight.
The convenience of being in the field, however, allows researchers to do all kinds of hands-on medical assessments and closely monitor how systems change during weightlessness. Such an analog also allows researchers to collect data on body changes from a larger number of people, as well as to draw firm conclusions about what they observe more quickly.
Microgravity on Earth?
Although dry immersion is more commonly used by Russian researchers, ESA’s SciSpacE team is testing to see how similar it is to actual spaceflight. Using VIVALDI, they hope to identify specifically what changes occur in the body in weightlessness, how long those changes take to occur, and how they compare to spaceflight and other ground-based microgravity analogues.
“Our first goal is to use the analogue to better understand how humans react and adapt physiologically, and to some extent psychologically, to such an extreme stimulus,” says Angélique, ESA Discipline Lead for life sciences. “It’s a good tool to better understand how astronauts adapt to spaceflight, and it allows us to test and validate countermeasures.”
The first stage of this experiment, VIVALDI I, had an all-female group of participants, to fill a gap in existing research. Along with VIVALDI II, the soon-to-be-started second stage involving male participants, the data collected will give researchers an idea of the stresses that microgravity places on astronauts of any gender, so that broadly effective mitigation approaches can be designed.
Impact beyond spaceflight
But it’s not just astronauts who benefit from this research. The research that helps us reach the Moon and Mars can also be translated into health care here on Earth. Understanding dry immersion deconditioning can also help researchers and physicians design new treatment approaches for patient populations, such as those with musculoskeletal disorders, those who are immobilized, and the elderly.
“At ESA, we really try to focus on this translational aspect as well,” Angelique shares. “If we can test countermeasures, like specific types of exercise or nutritional supplements, and find that they work well, perhaps health researchers could also consider testing them for populations of specific patients.”