In what could be a worrying discovery for the next generation of astronauts, physiologists have revealed that even a long-term program of low-intensity exercise in space is not sufficient to counteract the effects of prolonged weightlessness on the heart.
According to the British newspaper “Daily Mail”, the researchers examined data from retired astronaut Scott Kelly, who spent nearly a year on board the International Space Station (ISS) from 2015 to 2016.
The researchers found that he lost a mass in the left ventricle, one of the two large chambers in the lower part of the heart, despite the large amounts of exercise.
Microgravity in space means that the heart does not have to work as hard to pump blood around the body, which causes atrophy or a decrease in tissue, and this poses serious problems for astronauts during long-term space flight, as it reduces bone density as well, and increases The risk of bone fractures and muscle weakness.
“The heart is remarkably flexible and is particularly responsive to gravity or its absence,” said study lead Professor Benjamin De Levine at the University of Texas Southwestern Medical Center.
“We were surprised that even very long periods of low-intensity exercise did not prevent the heart muscle from contracting,” the professor emphasized.
Also, with the longer stays aboard the International Space Station and the increased likelihood of humans spending longer periods in space, there is a need for a better understanding of the effects of microgravity on heart function.
This study revealed a major hurdle facing future space exploration missions, including planned manned missions to Mars, by NASA in the 2030s and SpaceX as early as 2026.