[Avodah] When does mixed swimming mean?

[Moshe Y. Gluck]

MYG:
> It seems to me that swimming pools bring out a person's inner child to
> some degree (perhaps due to the relative weightlessness?) thereby
> leading to Kalus Rosh more so than, say, a formal dinner (even where
> alcohol is served). IOW, even if the visual aspects of Tzenius were
> totally absent there still might be an issue.
R' Joel Rich:
> Assumedly amusement parks do the same thing.

I'm not nearly as much an expert on amusement parks as swimming pools :-)
but I certainly see validity in that argument. Ice skating rinks? Mixed
sports? 

KT,
MYG