Astronauts turn out to suffer a level of bone loss that is completely irreparable after being in space for half a year
Astronauts who have been on a mission in space for more than 6 months suffer from bone loss equivalent to about 20 years of aging due to long-term microgravity, and recover only about half when they return to the ground. Was revealed in a new study. This discovery could pose serious problems for future manned flight missions to Mars.
Incomplete recovery of bone strength and trabecular microarchitecture at the distal tibia 1 year after return from long duration spaceflight | Scientific Reports
Astronauts suffer decades of bone loss from months in space, study reveals | Live Science
When staying in outer space for a long time, there is a problem that the muscles that support the weight are weakened by putting the body in a situation where there is almost no gravity. And like muscles, bones are important for supporting weight, and long-term microgravity can irreversibly weaken bones.
Previous studies have already shown that long-term stays in space can lead to muscle and bone weakness, and to mitigate this, astronauts use exercise equipment such as treadmills and ergometers daily 2 I am exercising for time.
How do you stay healthy at the International Space Station (ISS)? | JAXA Manned Space Technology Division
You can see Koichi Wakata, a Japanese astronaut, actually exercising on the ISS in the following movie.
'Weekly Wakata' (Vol.15) 'Introduction to strength training on the ISS' --YouTube
A research team at the University of Calgary in Canada evaluated the bones of 17 astronauts who stayed at the International Space Station. There were 14 male and 3 female astronauts, the average age was 47, and the length of stay on the ISS was 4 to 7 months.
To track astronaut bone deterioration and recovery, the research team conducted high-resolution quantitative CT for peripheral bone (high-resolution peripheral bone) on parts such as wrists, ankles, and shins before and immediately after the astronaut went to the ISS. Bone mass and bone density were calculated by scanning with a technique called HR-pQCT). In addition, follow-up surveys were conducted 6 and 12 months after the astronauts returned.
As a result, it was found that 16 out of 17 astronauts had not recovered their bone strength to the level before they left for space even one year after returning to the ground. In addition, it was found that eight astronauts who stayed in space for more than 6 months had 10 years of aging in their bones and their durability had dropped by 334 Newton (about 34 kg). ..
Bone can be broadly divided into two categories: bone cortex and spongy. The bone cortex is the hard part of the outside of the bone that makes up 80% of human bone mass. The spongy material is the remaining 20%, which has a dense structure like a mesh and reinforces the bone from the inside. If you stay in space for a long time, some of this sponge will disappear and the strength of your bones will decrease.
The research team says that future manned exploration vessels are expected to be even narrower than the ISS, so deadlifts , lower body exercises, jump exercises, etc. need to prevent bone loss.
Stephen Boyd, a professor of radiology at the University of Calgary, said, 'We know that spongy structures are lost during space flight, and when we return to Earth, new bone is formed, but its recovery capacity is very low. There is a possibility. '
Robert Sirsk, a former president and astronaut at the University of Calgary, said, 'Similar to adapting the body to space flight at the beginning of a space mission, it must re-adapt to the Earth's gravitational field at the end of the mission. I faced the problems of fatigue, light-headedness, and imbalance shortly after returning. It takes the longest time for bones and muscles to recover after space flight, but less than a day after landing. , I am now comfortable again as an astronaut. '
in Science, Posted by log1i_yk