The running suit Cathy Freeman wore when she won Olympic gold in Sydney has inspired an Australian-designed space suit, which has made it all the way to the International Space Station.
Known as the SkinSuit, the spacesuit was worn by Denmark's first astronaut Andreas Mogensen during his 10-day mission last month.
Worn over two days, the suit was tested in space to establish its ability to reduce the impact of zero gravity on the human body, in particular whether it could minimise the amount the spine stretched.
Astronauts' spines stretch by up to seven centimetres in space, a physiological change which causes mild to debilitating pain.
When in space, astronauts also lose up to 2 per cent bone mass a month, mainly around weight-bearing parts of the body such as the legs, torso and hips.
Designed at RMIT over more than 15 years by aerospace engineer James Waldie and colleagues, the skin-tight space suit is made of bi-directional elastics which mimic the "Earth loading" on the body.
The idea of a skin-tight spacesuit first came to Dr Waldie during the Sydney Olympics, when he was watching Cathy Freeman compete in the women's 400 metres in her running suit.
"I was watching and I thought if we re-engineer a skin-tight suit, it would bring physiological benefits to astronauts," he said.
Made in Italy, the suit has a vertical stretch that gradually increases from the shoulders to the feet, mimicking the load humans experience on Earth.
"When astronauts get into space, all of a sudden they are weightless and their bodies very quickly adapt to that extreme environment," Dr Waldie said. "This suit tricks the body into thinking you have stayed on Earth and therefore it stays healthy."
He said the skin-tight suit, similar in tightness to Lycra riding pants, was tailored for each astronaut to maintain the tension from shoulder to toe. Mogensen had to have his height and body circumference measured at one-centimetre intervals.
The suit underwent physiological tests at Kings College London, while researchers from the Massachusetts Institute of Technology also worked on its development before it went to the International Space Station.
In space, the suit was tested for comfort and mobility, which included a stint on the International Space Station's bicycle ergometer. Skin swabs were taken as part of hygiene tests and height measurements established the impact on the spine.
The performance of the SkinSuit in space is still being assessed by the European Space Agency, after Mogensen's return to Earth on September 12.
Pre-space testing showed it decreased pain in the cervical and lumbar sections of the spine. The cervical vertebrae are the thinnest and most delicate bones of the spine, while the lumbar vertebrae carry the upper body's weight while providing flexibility and movement to the trunk region.
"Based on what we have already seen, we would expect to have a reduction in the spinal elongation," said Dr Waldie, a senior research associate at RMIT.
He said the SkinSuit would be suitable for exploring other worlds – from the moon to Mars and beyond. It could also have more earthly applications, such as providing support for cerebral palsy or bedridden patients.
