Generally speaking, the national space station, whether it is a national or multinational joint space station, has a special exercise area. Of course, these exercise areas are different from gymnasiums seen on the earth, because there are many devices in gymnasiums on the earth, which use the weight brought by the gravity of the earth to promote the development of body muscles, or bring some stimulation to the muscles of the body to make them develop, but there is no gravity in space, so you can only carry weights manually, for example, when you board a bicycle, between gears.
Astronauts don't expect to stay in space for long. Basically, they have a service period. How long they stay in space will usher in the next wave of astronauts to take their place. Soon after. The country that was able to go into space about 15 years ago was surgery. At that time, the technology was more advanced, and now it is nothing. It is not difficult for a slightly older country to launch a manned spacecraft now. Especially for the European Union, the United States, the Russian Federation, China and other major countries in the world, launching some manned spacecraft is a very simple matter, and there is no need for everyone to be in the news. When we can't see them, they are silently maintaining the operation of the space station.
So generally speaking, they all have sports equipment in the space station, and they also have corresponding food to keep their nutrition balanced and effective sports equipment to promote the maintenance of body muscles, which will be replaced regularly. Different countries have different habits. In some countries, it may take three months, some half a year and some one month. They won't expect to stay in space for a long time.