A thorough understanding of the consequences of space flight on the human body and how to mitigate them is being provided by a study of bone loss in 17 astronauts who travelled aboard the International Space Station. This knowledge is essential in advance of potential ambitious future missions.
The study gathered new information on the extent to which bone mineral density can be recovered on Earth and the bone loss in astronauts brought on by the microgravity of space. The average age of the astronauts, 14 men and 3 women, was 47. Their missions in space ranged from four to seven months, with an average of roughly five and a half months.
An average of 2.1 percent less bone mineral density and 1.3 percent less bone strength could be seen in the tibia, one of the lower leg’s bones, a year after astronauts returned to Earth. Nine had a persistent reduction in bone mineral density that did not improve after the space mission.
“We are aware that long-duration spaceflight causes bone loss in astronauts. Leigh Gabel, a professor of exercise science at the University of Calgary, is the lead author of the study, which was published this week in the journal Scientific Reports. “What’s novel about this study is that we followed astronauts for a year after their space travel to understand if and how bone recovers,” she said.
During their six-month space missions, astronauts “had severe bone loss—a loss we would expect to see in older adults over the course of two decades on Earth—and they only recovered about half of that loss after one year back on Earth,” Gabel said.
Because bones that normally support weight on Earth do not do so in space, bone loss happens. According to Gabel, space agencies will need to increase nutrition and training regimens to help stop bone loss.
“Fine bone structures thin during spaceflight, and finally some of the bone rods separate from one another. The astronaut’s total bone structure is permanently altered, Gabel said. “Once the astronaut returns to Earth, the remaining bone connections can thicken and strengthen, but the ones that are detached in space can’t be repaired.
The astronauts included in the study have spent the last seven years in orbit. They were from the Canadian Space Agency, the European Space Agency, the Japanese Aerospace Exploration Agency, and the United States Space Agency (NASA). The report did not specify their countries.
Human body problems brought on by space travel are major considerations for space organisations as they design new explorations. For instance, NASA wants to send astronauts back to the moon, but the earliest that will happen is 2025. That might be a step toward future manned flights to Mars or a more protracted stay on the moon.
Muscle and bone are just two of the many physiological systems that microgravity impacts, according to Gabel.
Additionally, the cardiovascular system goes through numerous alterations. In the absence of gravity, astronauts undergo a fluid shift that results in increased blood pooling in the upper body. The cardiovascular system and vision may be impacted by this.
The greater their distance from Earth, the more radiation they are exposed to and the greater their danger of developing cancer, according to Gabel.
The study showed that longer space missions resulted both in more bone loss and a lower likelihood of recovering bone afterwards. Resistance training performed on the space station during flight proved crucial for halting the loss of muscle and bone mass. It was discovered that astronauts who performed more deadlifts during a trip than they typically would on Earth were more likely to recover bone.