Question: Why and how do muscles degrade in space, and what effect did this have on the worms?

Emma Markham answered on 13 Jun 2019:

On Earth we are constantly using our muscles to hold ourselves up against gravity (otherwise we would be lying on the floor all the time). So by using these muscles all the time it means they are kept strong, if you don’t use a muscle then it will degrade and become smaller. This is why exercise builds muscle, because the more you use it the bigger it will get.

So in space we don’t need to use out muscles very much, because we don’t have to fight gravity and can just float around, which is great but it’s a problem if we loose our muscles and want to come back to earth, because walking and breathing will be hard. This is why astronauts need to do lots of exercise in space so they retain their muscles and can still walk when they come back to earth.

Worms are made of lots of muscles, and so are very good if we want to study the impact of space and no gravity on how muscles degrade, so we sent some worms into space for a period of time and then look at how their movement changed and how ti changed when they can back to earth. We can look at different genes associated with muscle growth and retention, or drugs we can use to help retain these muscles. This is important if we want to travel to Mars, as we will need to live in space for a long time. But this is also important for old people on Earth, because they also loose muscles as they age, and for people with muscle loss diseases.

So, the worms which were sent to space began moving differently, and they had trouble moving when they came back to earth, because they had lost useful muscles which they needed to regrow.