L’bones caused by the absence of similar to it has long been studied on board the stations . Floating there is pleasant, but the they must engage in several hours a day of physical exercise to limit the damage of this inactivity of the locomotor system. What is less known is how long it takes them to recover after returning to earth.
Using new 3D imaging techniques, a study of 17 astronauts from the(ISS), published in the journal shows that recovery remains incomplete even after one year.
Work began in 2015 at the initiative of Steven Boyd, director of the McCaig Institute for Bone Health at the University of Calgary in Canada. With his colleagues, they imagined the skeletons of 14 men and 3 women before theirsupon their return to Earth, then 6 months and another 12 months after their landing.
In particular, they playedbones of (which supports almost all the weight of the body) and radius (forearm) to evaluate its density e at the fracture. When calculating the effects of physical exercises practiced in and back to Earth.
What are the results after the return of the astronauts to Earth?
Result: a year after the flight, 16 astronauts showed aincomplete tibia, which had lost up to 2% of his compared to the pre-flight period. The longer the stay it had been a long time (6 to 7 months) the more the bone system was damaged. After a year, 9 of the astronauts had not fully recovered. Damage comparable to a decade of bone loss on Earth, or more.
“We also show that the bone architecture is permanently alteredDr Steven Boyd, co-author of the study, told AFP. Think of the Eiffel Tower and all its metal rods – in space we lose some of its rods. When we return to Earth, we can repair those that remain but we don’t create new connections. “continues the researcher.
The challenges of the astronauts
” Theit is the most drastic physical inactivitycomments Guillemette Gauquelin-Koch, head of space medicine at Cnes. Even with 2 hours of sport a day it’s like being confined to bed for the remaining 22 hours “adds the doctor, who did not take part in the study.
The inhabitants of the ISS had a new machine developed by theA red (Advanced resistive exercise device), which exerts a resistance similar to gravity on the body, permitting legs, biceps work, abs … “We should be doing more exercises like this to reduce bone loss.”Steven Boyd recommends.
For the futureto Mars – from much longer than 6 months – it is still an obstacle, which adds to the problems of cosmic radiation and the psychological impact of a long confinement. “It won’t be easy for the crew to set foot on Martian soil when they arrive … it’s very debilitating”according to Dr. Gauquelin-Koch.