If you are lucky enough to come to Sino-British College, there is a free gym on the second floor of the East Building, which is separate for men and women. Very easy to use, and the equipment was just bought this year. But because it is free, there are more people.
If not, you can only go to a nearby gym. It is very expensive to get a card. Girls in our major usually get a yoga annual card, about 1200.