Is it ok to dress immodestly when im in dance lessons?

I am lds (mormon) and im dancing at the stadium of fire. We have to practice the dances all day long in the very hott weather and i really want to be modest but where its going to be so hott i dont know what to do. If you know of a lds general conference talk or something where it says when its okay not to be modest that would help me a ton! thank you!(: