Study shows decreased bone density in travelers who spend months in space. The researchers also found that a year after the travelers returned to Earth, the decrease in bone density did not resolve. The scientific community is now concerned that this could be a challenge for longer journeys such as future Mars missions.
Previous studies have found that for every month that travelers spend in space, their bone density decreases by one to two percent. In space, there is no pressure on the legs when walking or standing due to the lack of gravity. This causes a decrease in bone density.
The study was conducted on the last 17 astronauts on the International Space Station. The researchers measured their bone density before they left for the space station, while on the station, and after they returned.
In space, travelers lose bone density that would take decades to lose on Earth. The study found that the decrease in bone density of the shinbone, the large bone below the knee, was not compensated for by the travelers a year after returning to Earth. The study was led by Steven Boyd of the University of Calgary in Canada.
Astronauts who spent seven months on the International Space Station took the longest to recover. Those who spent longer in space took longer to recover. Boyd also expressed concern that travelers may face more of these problems on long-duration space missions such as the Mars mission.
Human missions to Mars can often require travelers to stay in space for several years. Will astronauts face more problems as time passes? We cannot say for sure now. It is possible that sometimes it will get fixed after some time. Sometimes bone density may continue to decrease. But will it be so lost that there is not even a little left? Steven Boyd says such a situation is unthinkable.
These problems can be reduced by doing some exercises. Robert Trisk is a Canadian astronaut who spent 205 consecutive days in space. Robert also testifies that his muscles and bones took the longest to get back into shape. Future astronauts may face challenges unknown to the scientific world. Evidence of this is demonstrated by the study of bone density.
English Summary: Astronauts Struggle to Regain Decades’ Worth of Bone Density After Space Travel