Buenos Aires is the second largest metropolitan area of South America after San Pablo, but you will find a lot of contrast in the city, skyscrapers, parks, and residential areas. If you go to the west part of the city you are going to find neighborhoods as Colegiales, Villa Crespo and Saavedra. In these places you will feel that you left the city and you entered to a small town where all the neighbors know each other.
Inside these residential areas you will find public sports centers where people go to practice several sports for free and in summer they go to enjoy the pool.
If you are in the middle of a long journey and you want to practice some sports, polideportivos, as we know it in Argentina, are the solution. In the afternoon you will find a lot of people playing football, basket, volley, and other sports. You can join for free and celebrate a nice cultural interchange.
One sport center close to the center of BA and Palermo is Polideportivo Colegiales. Have a nice time!