Playing in hot and humid conditions may make you perspire more and dehydration becomes a problem. I find high heat and high humidity also make it harder to breathe which doesn't help the cause. And high humidity will slow evaporation of sweat which is our cooling mechanism.
Drink a lot of water and/or gatorade or equivalent to keep hydrated and your electrolytes up. Probably not a great idea to play for three hours in those conditions, two hours should suffice.
Last edited by Fearsome Forehand; 08-31-2012 at 12:30 PM.