Long-term exposure to microgravity leads to loss of bone density and New research shows the worrying extent to which this is happening, noting that astronauts may never fully recover.
“The detrimental effect of space travel on skeletal tissue can be profound,” says the opening sentence of new research published today in Scientific Reports. Profound is right. That Study led by kinesiologists Leigh Gabel and Steven Boyd of the University of Calgary found that astronauts whoLong-term spaceflights (ie, missions lasting more than three months) show signs of incomplete bone recovery even after a full year on Earth. Long-Long-term missions appear to lead to premature aging of bones, particularly bones in the weight-bearing lower extremities.
“We found that a year after spaceflight in most astronauts, the load-bearing bones have only partially recovered,” Gabel said in a statement. “This suggests that permanent bone loss from space travel is roughly equivalent to a decade of age-related bone loss on Earth.”
The good news, if there is any, is that space-based resistance training can serve to limit bone loss and speed Restoration. previous research from the same team showed that “astronauts are more likely to preserve their bone density and strength when they increase the volume of lower body resistance training in flight compared to pre-flight,” the researchers write.
New research shows how dependent we are on gravity to maintain our bone strength. Every day is a constant struggle against gravity, but all this work is good for our body as it continuously strengthens our bones. In space, however, astronauts float around with hardly anyone physical resistance, resulting in a gradual loss of bone density.
“Bone loss occurs in humans — as we age, get injured, or in any scenario where we can’t move the body, we lose bone,” said Gabel. “It’s incredibly rare to understand what happens to astronauts and how they recover. This allows us to observe the processes that take place in the body in such a short time.”
The team traveled to NASA’s Johnson Space Center in Houston, Texas to conduct the study. A total of 17 international astronauts (14 men and three Women) have been studied, all of which have conducted long-duration missions at some point in the past seven years. The astronauts were evaluated prior to their ISS spaceflights and then six and 12 months after their return to Earth.
The team made bone scans of specific anatomical areas, namely the tibia or tibia and forearm. This allowed the scientists to assess the susceptibility of these bones to fracture (or “failure load,‘ popularly spoken by kinesiologists) and the amount of bone mineral content and the thickness of bone tissue. she also recorded the astronauts’ training routines during and after their space Missions including exercises like deadlift, running on a treadmilland cycling.
Of the 17 astronauts studied, 16 had incomplete recovery of their shins (the measurements of their forearms didn’t really differ a year after spaceflight). On average, the astronauts displayed a tibial fracture load capacity of 10,579 Newtons prior to their spaceflights, but this dropped to 10,084 Newtons upon their immediate return to Earth, a loss of 495 Newtons. While the astronauts managed to partially recover in the year after their return, they were still 152 newtons below their pre-flight tibia stress levels.
Her bone density also took a hit. The astronauts had an average bone density of 326 milligrams per cubic centimeter before their time in spacebut that fell to 282.5 mg per cubic centimeter on her return – a drop of 43.5 mg per cubic centimeter.
“Our results indicate that microgravity causes irreversible damage to bone strength, density and trabecular bone microarchitecture,” the scientists write in their study. The trabecular bone is a “highly porous form of bone tissue organized into a network of interconnected rods and plates“, whose function is provide strength and direct external stress away from the jointsaccording to independent research.
Unsurprisingly, the bone measurements deteriorated depending on the duration of use. The eight astronauts who stayed on the ISS for more than six months recovered significantly less than those who had been on shorter missions, according to the study. At the same time, the astronauts who recovered the most tibial bone mineral density performed best Deadlift in flight.
“As space constraints will be a limiting factor for future explorer-class missions, the training devices must be optimized for a smaller footprint,” the scientists write. “Resistance training (especially deadlifts and other lower body exercises) will remain a mainstay to mitigate bone loss; However, adding jumping exercise to on-orbit regimens can further prevent bone loss and reduce daily exercise time.”
These are important insights, especially as NASA, through his upcoming Artemis program, wants to build a sustainable and enduring presence on and around the moon. The new research also speaks to future human missions to Mars, which will also involve longer stays in space. In addition to muscle atrophy and the loss of bone strength that microgravity adversely affects heart, Eyes, Brain, spine, cellsand overall physical fitness. It is vital that we understand all of the risks associated with space travel and the best ways to mitigate them.
More: Missions to Mars shouldn’t exceed four years due to radiation risks, scientists say.