Study focused on bone loss, its effects on astronauts and their return to Earth
Study focused on bone loss, its effects on astronauts and their return to Earth
A study of bone loss in 17 astronauts who flew aboard the International Space Station is providing a more complete understanding of the effects of space travel on the human body and the steps to mitigate it, vital knowledge ahead of potentially ambitious future missions.
The research gathered new data on bone loss in astronauts due to the microgravity conditions of space and the extent to which bone mineral density can return to Earth. This included 14 male and three female astronauts, average age 47, whose missions in space ranged from four to seven months, averaging about 5-1/2 months.
A year after returning to Earth, the astronauts displayed an average of 2.1% lower bone mineral density in the tibia — one of the bones in the lower leg — and 1.3% less bone strength. Experiencing permanent loss, Nine did not recover bone mineral density after space flight.
“We know that astronauts lose bone on long-duration spaceflight. What’s novel about this study is that we followed astronauts’ spaceflight for a year to understand how and how bone heals.” ,” said Professor Leigh Gabel of the University of Calgary, an exercise scientist who was the lead author of the research published this week. Journal Scientific Reports.
Gabel said, “Astronauts experienced significant bone loss during six months of space flights — damage that we would expect to see in adults older than two decades on Earth, and they did that loss a year ago on Earth.” Only about half of it was recovered.”
Bone loss occurs because bones that normally carry weight on Earth do not carry weight in space. Gabel said space agencies need to improve countermeasures — exercise regimes and nutrition — to help prevent bone loss.
“During spaceflight, the fine bone structure thins, and eventually some of the bone sticks become disconnected from each other. Once the astronaut is back on Earth, the remaining bone connections can become thicker and stronger. , but those that are disconnected in space cannot be rebuilt, so the overall bone structure of the astronaut is permanently altered,” Gabel said.
The study’s astronauts flew on the space station over the past seven years. The study did not state their nationality but they were from the US space agency NASA, the Canadian Space Agency, the European Space Agency and the Japan Aerospace Exploration Agency.
Space travel presents various challenges to the human body – major concerns for space agencies as they plan for new exploration. For example, NASA is aiming to send astronauts back to the Moon, Now a mission is planned for 2025 as soon as possible. This could be a proposal for future astronaut missions to Mars or a longer duration presence on the lunar surface.
“Microgravity affects many systems of the body, the muscles and bones,” Gabel said.
“The cardiovascular system also experiences many changes. Without gravity pulling blood toward our feet, astronauts experience a fluid change that causes more blood to pool in the upper body. This can affect the cardiovascular system and vision. could.
“Radiation is also a major health concern for astronauts because the farther they go from Earth, the greater their exposure to the Sun’s radiation and the increased risk of cancer,” Gabel said.
The study showed that longer space missions resulted in greater bone loss and reduced chances of bone recovery later. In-flight exercise — resistance training aboard the space station — proved important for preventing muscle and bone loss. Astronauts who performed more deadlifts than typically performed on Earth were found to be more likely to have bone recovery after their mission.
“There’s a lot we still don’t know about how microgravity affects human health, particularly on space missions longer than six months and on long-term health outcomes,” Gabel said. “We really hope that bone loss will eventually plateau on longer missions, that people will stop losing bone, but we don’t know.”