原文已被隐藏，你可用 快捷键 - 或点击 显示原文 按钮来查看原文
第1段
1 .This is Scientific American 60-Second Space. I'm Sophie Bushwick. Got a minute?
该句暂无译文！
2 .When astronauts float weightless in space, their muscles don't need to work as hard as on Earth.
该句暂无译文！
3 .Muscles therefore atrophy during a long mission, which can cause trouble when space travelers return home.
该句暂无译文！
4 .But what happens to that most vital of muscles, the heart?
该句暂无译文！
5 .To find out, 12 astronauts learned how to do ultrasound scans of their hearts.
该句暂无译文！
6 .Then they recorded the organ's shape before, during and after a stint on the International Space Station.
该句暂无译文！
7 .The scans showed that, while in microgravity, the astronauts' hearts deformed into more spherical shapes.
该句暂无译文！
8 .Back on Earth, they stretched back into their usual elongated forms.
该句暂无译文！
9 .The work was presented at the annual scientific session of the American College of Cardiology.
该句暂无译文！
10 .Knowing how weightlessness changes the heart could help mission planners prevent long-term damage to astronauts' cardiovascular systems due to long space voyages.
该句暂无译文！
11 .Astronauts on the space station already perform specific exercises to keep their weight-bearing muscles toned.
该句暂无译文！
12 .Similarly well-designed workouts might keep hearts both in shape, and in the right shape.
该句暂无译文！
13 .Thanks for the minute, for Scientific American 60-Second Space. I'm Sophie Bushwick.
该句暂无译文！