If any sport can make you sweat your guts out in Barcelona, it's trying to find gym classes in Catalan. In the municipal sports centers (CEM), which are public sports facilities, Catalan appears to be the official language (on signs, on the website, and online). However, this directive doesn't translate into the classes.
Laia does at the Joan Miró CEM in the New Left of Eixample and certifies that "many teachers are Catalan speakers and greet students in Catalan, but classes are generally in Spanish, except for swimming with the little ones." If you ask them by phone, the receptionist first responds that the classes are "in Spanish," then corrects them by saying they are "in Catalan," and finally offers to switch to Spanish if anyone doesn't understand..
Practicing sports in Catalan at Barcelona gyms? Mission impossible.

If any sport can make you sweat your guts out in Barcelona, it's trying to find gym classes in Catalan. In the municipal sports centers (CEM), which are public sports facilities, Catalan appears to be the official language (on signs, on the website, and online). However, this directive doesn't translate into the classes. Laia does bodypump at the Joan Miró CEM in the New Left of Eixample and certifies that "many teachers are Catalan speakers and greet students in Catalan, but classes are generally in Spanish, except for swimming with the little ones." If you ask them by phone, the receptionist first responds that the classes are "in Spanish," then corrects them by saying they are "in Catalan," and finally offers to switch to Spanish if anyone doesn't understand.