I am a member of a gym here and I was finishing getting changed in the locker rooms, as usual, when there was a knock on the door and a girl of about 17 or 18 marched straight in. I was the only man in there at the time. She was a member of a ballet club which uses the facilities and was looking for a male member and she asked me, in Swedish, if I had seen him. I said I hadn't and I told her off in quite strong terms about barging in like that. She protested that she had knocked, but I pointed out that a knock does not mean that users know that a female is the person knocking, and that those of us getting changed would not have had any time to cover our modesty. I also pointed out that, had the situation been reversed and I had barged into the female locker room in that fashion, I have no doubt that some female users would have been less than happy. She tried to defend herself with something about the fact that, in ballet theatres etc, there is usually communal changing for both sexes (that was news to me!!) and nobody is bothered. I pointed out that this was a gym, not a ballet threatre, and if dancers wanted to continue to use the facilities, they should respect the general rules which apply to gyms.
While I appreciate that nudists would perhaps be less bothered than I was, but I am sure most would agree with me that she was in the wrong. The experience did leave me a bit shaken; I have never thought twice about getting changed in this locker room before because it was a strictly males-only environment, and now I am tempted to get changed under a towel, as I would on a public beach, which is crazy. I won't do that, of course, but I will certainly be making a complaint if this happens again.