Seek the nearest gym in Xicheng District, Beijing.
Actually, I don't know where you live. Anyway, I live near Xinjiekou and Liuhai Hutong. There is a community place in Liuhai Hutong, which is open to the public, and there is a gym underground. If it's convenient, you'd better contact there. There is also a library, where you can play table tennis, learn to dance and sing. I think it's nice there.