We feel dizzy when we stand up too quickly because gravity causes blood pressure to dip momentarily. Imagine the physiological adaptations our body would have to make for going into space and back.
Space is a hostile environment for humans, even more so than mountain peaks or deep waters. In 2016, British astronaut Tim Peake had to be carried from the landing module on his return from his trip to the International Space Station. The challenges of extended space travel are complex and affect most of the systems of the body.
Astronauts already travel into space successfully. Such extended space flights have given physiologists the opportunity to investigate responses to this environment and consider ways to ensure survival on even longer missions. This research can also help us understand some of the medical conditions in people living on Earth. Hence as a space physiologist, your work is not limited to outer space.
Space is a microgravity environment, which means some mechanical forces on the body that we are used to on Earth are absent or reduced in space. This causes our body systems to work differently. For example, Earth’s gravity causes blood to pool in our lower limbs. The heart works hard to pump the blood up to the brain. In space, blood pools in the upper body (chest and head) instead and the heart does not pump as strongly. When astronauts come back, it can be challenging for the cardiovascular system to return to normal.
Less blood being pumped to the brain means difficulty in standing without fainting. This is exactly what happens to people who feel dizzy after bed rest or change of position – because their blood pressure has dropped too low. Space physiologists study various ways in which the body can adapt better to these changes.
Another important example is muscle loss. In a microgravity environment, less force is exerted on muscles so they do not have to work as hard. Muscles deteriorate when they are not used. Spaceflight studies have shown up to 24% loss in calf muscle after more than 100 days in space. This means that standing upright on Earth again becomes much harder and requires rebuilding the lost muscles. This condition is also experienced by people on Earth who are prescribed bed rest or have reduced movement. Space physiologists’ research may help to develop measures that minimise these effects both in space and on Earth.
The space physiology research happening today will inform future developments. Will we make it to Mars and beyond? If you are passionate about advancements in human endeavour, then this may be the field for you.
How do I get involved in space physiology research?
An undergraduate degree in any life science subject (including physiology, biomedicine, medicine, sports science, neuroscience, genetics etc.) will open the door to a career in physiology research.
Following this, you will have to apply for a PhD (Doctor of Philosophy) if you wish to pursue a research career in a university. This involves a substantial research project, typically 3-4 years in length, and training in scientific as well as transferable skills. These are usually fully funded by Research Councils, charities or increasingly industry.
Graduates often complete a Master’s degree before undertaking a PhD. Master’s degrees like a MSc (Master of Science), MRes (Master of Research) and, increasingly, integrated Master’s degrees (e.g. M.Biol or Master of Biology) help to develop a greater understanding of a particular scientific area. This will give graduates a better grounding and make them more competitive for PhD positions.