Hair at the start of day 3. This is the side I sleep on.
I rediscovered a great multi-day combo that withstood 3 days of an 11-hour per day fitness training intensive called a NIA White Belt. A lot of sweating was done - 2 formal classes a day plus many more moving and sweating opportunities during the training. The kind of workshop that requires a change of workout clothes from the skin out, or you walk around with wet clothing.