Most Helpful Guy
Go for it. I always thought it was more trashy to have your panties showing than if you dont have any material there like a thong. When i ran track and would stretch with the girls their underwear would show. If they were wearing thongs then it would just be skin and not underwear.
Most Helpful Girl
Wear whatever is comfortable for you, who cares about other peoples opinions on how slutty or not slutty you are because of what you wear? When you get sweaty though usually your underwear will absorb some of it, I don't know how much a thong will absorb haha. Maybe try for cheeky underwear for the best of both worlds?