For the past twenty years, Tamara Franz-Odendaal has been studying how space travel affects the human skeleton.
Due to the lack of gravity in space, astronauts lose bones when they return to Earth.
“We always think of it as the scaffolding that holds the body together, but it’s a really dynamic tissue,” said Franz-Odendaal, a professor at Mount Saint Vincent University.
Using a device called a random positioning machine, which simulates microgravity experiments on Earth, Franz-Odendaal is conducting a two-year research project to better understand how bones respond to the lack of gravity. The research has implications for improving the treatment of bone disorders, such as osteoporosis.
Franz-Odendaal’s research uses zebrafish placed on a platform and then rotated randomly to try to simulate zero gravity.
This device, called a random position machine, is being used to simulate the absence of gravity in space. (Submitted by Tamara Franz-Odendaal)
She said zebrafish are commonly used as a model organism in developmental biology and “as an actual model for many human diseases because the cell types are very similar, and this is also true for the skeleton.”
Canadian astronaut David Saint-Jacques knows firsthand about bone loss after space missions. He spoke to CBC News from the Canadian Space Agency headquarters in Longueuil, Que. Saint-Jacques headed to the International Space Station for a 204-day mission starting in late 2018.
Canadian Space Agency lead crew member David Saint-Jacques gestures to the International Space Station before the launch of the Soyuz MS-11 spacecraft in Kazakhstan on December 3, 2018. (Dmitri Lovetsky/The Associated Press)
People may imagine astronauts walking triumphantly when they return to Earth, but that is not the reality.
“It’s very frustrating,” he said, “because you’d think it’s like riding a bike. ‘Hey, I’m going to be a wreck again.’ No, getting used to gravity is harder than adapting to space, even though that’s the first time you’ve been there and evolution hasn’t prepared us for it.”
Photos from his return in 2019 show him being carried by others.
Ground personnel help Saint-Jacques exit the Soyuz MS-11 capsule shortly after landing in a remote area outside Zhezkazgan, Kazakhstan, on June 25, 2019. (Alexander Nemenov/AFP via Getty Images)
He lost his sense of balance during the mission and was prone to burns because space changes the way blood flows.
In space, blood flows equally to different parts of the body because there is no gravity. On Earth, more of it must go to the brain, but the proper blood flow does not return immediately.
‘Guinea pigs perfect for medical research’
Saint-Jacques, who was a doctor before becoming an astronaut, said the changes astronauts make to their bodies in space make them ideal to study for medical research.
“They happen very quickly and in very young people who are otherwise in perfect shape,” he said. “We are, like, the perfect guinea pigs for medical research.”
In addition, it is easier to study these changes because the astronauts do not have other medical conditions, unlike an elderly person who may have some health problems, Saint-Jacques said.
Saint-Jacques said astronauts do a lot of exercise while in space.
Ground personnel transport Saint-Jacques after he returns to Earth. (Alexander Nemenov/AFP via Getty Images)
“If we are not careful, because there is nothing to weigh, you do not use your bones that much,” he said. “So if you are not careful, they will get very weak. That’s why we do a lot of exercise in space.”
Despite their performance, astronauts struggle to adjust to life on Earth. He said it took many months for him to feel back to where he was before he could resume hobbies such as basketball and skiing.
“I’m on [Earth] for all my life, and all my ancestors for that matter, it should come back like that,” he said.
“That’s not how it works.”