Wearing a sweater is not the same as "hot yoga"

I was just in Puerto Rico and decided to work off some of my non-stop eating with a quick jog on the treadmill. Next to me was a women dressed head to toe in heavy clothing and running furiously. This is PR. It is 85 degrees and there is no air conditioning on. It is already boiling in the gym (so hot I decided not to work out and to walk the beach for exercise instead). But this women is sprinting with all her strength and the sweat is pouring off her body as she runs. I would swear her outfit looked like something I wear wear to do errands in the dead of winter in NY. Hmmm, wonder what she wears when there is air conditioning!