What not to do before a 3 day trek...
Number 1: Eat fried street food in multiple locations within 30 minutes in the afternoon
Number 2: Drink consecutive very sweetened masala teas (after eating the fried food)
Number 3: Go have beers
Number 4: Skip dinner and stay at a different bar (than the previous one) for 2 hours drinking Mandalay (local) rum
Number 5: Eat 2 bowls of noodles for under $2 late night without knowing exactly what's in them (very fishy)
Avoid all of these, and enjoy your trek!
Caveat* While drinking rum for 2 hours DO donate to the bar's local charity