I got a swimming card in Jingti, east of Warwick Bridge. It can swim, exercise, table tennis, badminton, billiards and so on. It is an old-fashioned gym with acceptable hardware, which is much cheaper than ordinary fitness clubs. You can go and have a look.
Jingti fitness center
Address:? No 1 Nanxinyuan, East Third Ring Road, Chaoyang District (near Warwick Bridge)?
Telephone:? 0 10-873 16976