Evrim Yazgin
Cosmos science journalist
Astronauts can sometimes grow up to 8cm after they’ve been in space, and now Australian health specialists are working with NASA to make their work less of a pain in the back.
Due to lower gravity in space, astronauts often suffer muscle, bone and back problems.
“On Earth, when we are upright, gravity loads the spine and this loading is important for maintaining the health of spinal tissues,” says Professor Julie Hides. “In the case of astronauts in microgravity, the intervertebral discs can imbibe fluid and the spinal curves flatten, resulting in lengthening of the torso. Astronauts can come back to Earth 5-8 centimetres taller,” Hides says.
Hides from the University of Griffith’s School of Health Sciences and Social Work and Professor James Elliott, Director of Sydney’s Kolling Institute, have been invited to contribute their expertise in musculoskeletal health at the Johnson Space Centre in Houston, Texas.
While some might like the idea of gaining some extra height, it’s not all good news for astronauts, who are predisposed to muscle atrophy (loss of muscle), bone loss and spinal pain.
Hides worked with the European Space Agency for 20 years. The spinal health expert presented to NASA results from 3 prolonged bedrest studies which simulate the decreased gravitational load on the spine.
The studies involved volunteers lying down at an angle of 6° for 60 days without rising.
Research was also presented on the effects of microgravity on astronauts.
Gravity on the International Space Station, for example, is about 89% of that on Earth. But, because the ISS is in low Earth orbit, the astronauts aboard and the station itself experience “weightlessness.”
Hides worked with NASA flight surgeon Dr Rick Scheuring to develop a way to take medical images of the trunk muscles of astronauts while in space.
“We were establishing an imaging protocol that would allow one astronaut to image another astronaut on the International Space Station,” Hides says.
Ultrasound is small and compact, and can show how the muscles contract in real time.
“While we have had access to ultrasound images of muscles before and after six months on the International Space Station, monitoring astronauts while in space will allow assessment of how quickly muscle size decreases, thus providing important information to allow development of appropriate exercise interventions.”
Elliot says: “NASA has expressed an interest in our MuscleMap program, which is a revolutionary technique to automatically assess or measure whole-body skeletal muscle composition using high-resolution MRI.
“The MuscleMap program could be an assessment tool to help target more effective ways to improve their pain and performance when they’re in space, when they get home, and in preparation for future missions.”
Hides says that, while directly beneficial to astronauts, the research could be translated to helping patients suffering musculoskeletal conditions on Earth.
