For me, I am a girl and I used to swim when I was young.. I always remove my swimming suit to take shower or get change in the changing room... I think it is ok to do so...
But, I understand that there are a lot of gay guys stay in the male changing room at the swimming pool... be careful of those people... if u see somebody remove all their clothes but their eyes are always looking around, I think there are some problems with them....take care