The life support system installed in the space station helps astronauts live in space for extended periods of time. While in space, the life support system provides oxygen and filters out the carbon dioxide exhaled by the astronauts. In addition, astronauts go through rigorous training regimens to ensure that their bodies can handle the conditions.
Since most astronauts do not spend as much time on their feet while in space as they would on Earth, their hearts have to work extra hard against gravity to move blood around their bodies. As a result, astronauts have to exercise in space each day to maintain strength in their muscles and bones. When it comes to staying clean is space, astronauts use a personal hygiene kit that contains toothbrushes, toothpaste, combs, brushes and shavers. These kits also come with specially formulated soaps and shampoos that do not require the use of water.
In order to keep the space station clean, astronauts must wipe the walls, floors, and windows using a soap that kills germs. There are four trash bins on the Space Shuttle: three for dry trash and one for wet trash. Lastly, when an astronaut goes to the toilet, the solid waste is treated to prevent any bacterial growth, and then it is dried and dumped into space.