Astronauts are in weightlessness in space, that is, ordinary weightlifting. Ordinary items can be easily picked up. So we can only train in other ways.

Because if you don't train, it will have a great influence on the muscles of astronauts.

Especially bones, there is gravity on the earth, so people's waist and legs should support the whole body. After being in space, without gravity, waist and legs, it's like going back to before liberation. If this continues for too long, your health will definitely go wrong.

So exercise to maintain the function of waist and legs.

For example, through the zipper, increase friction. Because there is no gravity in space, we can only move by friction and increasing resistance.

For example, running, with the help of some things, can increase personal pressure before running on it. If you exercise your arm strength, it will directly increase the resistance at the other end of the rope, so you can exercise.