This article is from the source 'rtcom' and was first published or seen on . It last changed over 40 days ago and won't be checked again for changes.

You can find the current article at its original source at https://www.rt.com/news/519476-gravity-heart-weightlessness-health/

The article has changed 3 times. There is an RSS feed of changes available.

Version 0 Version 1
Why sleep pods are science fiction: Long-term space travelers need high-intensity exercise to protect their hearts, study says Why sleep pods are science fiction: Long-term space travelers need high-intensity exercise to protect their hearts, study says
(5 months later)
The prospect of sleeping all the way to Mars will need to overcome one critical Earthbound reality – the human heart needs high-intensity exercise to offset the effects of zero gravity, researchers say.The prospect of sleeping all the way to Mars will need to overcome one critical Earthbound reality – the human heart needs high-intensity exercise to offset the effects of zero gravity, researchers say.
The human heart shrinks when it is in a zero-gravity environment for a prolonged period and low-intensity exercise does not do enough to reverse the damage. Here on Earth, gravity plays a key role in maintaining the size of the heart, researchers from the University of Texas say, so long-term exposure to weightlessness adversely affects the heart’s ability to function.The human heart shrinks when it is in a zero-gravity environment for a prolonged period and low-intensity exercise does not do enough to reverse the damage. Here on Earth, gravity plays a key role in maintaining the size of the heart, researchers from the University of Texas say, so long-term exposure to weightlessness adversely affects the heart’s ability to function.
"The heart is remarkably plastic and especially responsive to gravity or its absence,” said Dr. Benjamin D. Levine, the study’s senior author and a professor of internal medicine at UT Southwestern Medical Center."The heart is remarkably plastic and especially responsive to gravity or its absence,” said Dr. Benjamin D. Levine, the study’s senior author and a professor of internal medicine at UT Southwestern Medical Center.
The study team, whose findings were published in the journal Circulation on Monday, looked at data from NASA astronaut Scott Kelly as he orbited Earth on the International Space Station from 2015 to 2016.The study team, whose findings were published in the journal Circulation on Monday, looked at data from NASA astronaut Scott Kelly as he orbited Earth on the International Space Station from 2015 to 2016.
This was then compared to data from French long-distance swimmer Benoit Lecomte, who spent six hours a day swimming part of the Pacific Ocean in 2018, to gauge the long-term effects of weightlessness. Researchers believe water immersion is an excellent model for weightlessness since water offsets the effects of gravity, especially in a prone swimmer such as Lecomte.This was then compared to data from French long-distance swimmer Benoit Lecomte, who spent six hours a day swimming part of the Pacific Ocean in 2018, to gauge the long-term effects of weightlessness. Researchers believe water immersion is an excellent model for weightlessness since water offsets the effects of gravity, especially in a prone swimmer such as Lecomte.
Doctors performed tests to measure the health and effectiveness of both men’s hearts before, during and after each embarked on their respective expeditions. Kelly spent 340 days on the ISS and exercised on a treadmill and stationary bike for at least an hour daily, while Lecomte spent six hours swimming in a prone position.Doctors performed tests to measure the health and effectiveness of both men’s hearts before, during and after each embarked on their respective expeditions. Kelly spent 340 days on the ISS and exercised on a treadmill and stationary bike for at least an hour daily, while Lecomte spent six hours swimming in a prone position.
The scientists reported that both men lost mass from their left ventricles, which also reduced in size. The diameter of Kelly’s left ventricle dropped from 5.3cm to 4.6cm (2 inches to 1.8 inches); Lecomte’s shrank from 5cm to 4.7cm.The scientists reported that both men lost mass from their left ventricles, which also reduced in size. The diameter of Kelly’s left ventricle dropped from 5.3cm to 4.6cm (2 inches to 1.8 inches); Lecomte’s shrank from 5cm to 4.7cm.
The study said that each time a person sits or stands, gravity draws blood into the legs. The work the heart does to keep blood flowing as it counters gravity helps it maintain its size and function – and removing gravity effects causes the heart to shrink.The study said that each time a person sits or stands, gravity draws blood into the legs. The work the heart does to keep blood flowing as it counters gravity helps it maintain its size and function – and removing gravity effects causes the heart to shrink.
Like this story? Share it with a friend!Like this story? Share it with a friend!
Dear readers and commenters,
We have implemented a new engine for our comment section. We hope the transition goes smoothly for all of you. Unfortunately, the comments made before the change have been lost due to a technical problem. We are working on restoring them, and hoping to see you fill up the comment section with new ones. You should still be able to log in to comment using your social-media profiles, but if you signed up under an RT profile before, you are invited to create a new profile with the new commenting system.
Sorry for the inconvenience, and looking forward to your future comments,
RT Team.