The Impact of Microgravity on the Human Body

There are a few things that people find when astronauts come back from the International Space Station for example. One of them is decreased bone density by about one one or two percent per month which is quite significant if you're up there for several months at a time. Your muscle mass goes down obviously because you don't have to fight gravity all the time so you kind of atrophy. This is a particular problem with the heart because normally here on Earth the heart has to pump blood upwards to the head but in space you don’t have to do that and it starts to become a problem. It's just it's hard to turn into maths speaker I think.