newfound respect for runners in SE Asia.

Thanks!  You did better than me--my first run in Vietnam, I think I made it 30 minutes and puked!  I have worked up to where I can do HM and Olys in 30-38 degree heat and not die (though cramp and suffer is kind of a given). It has taken several years of training and lots of experimentation!

The body does adapt, to some extent--I think you sweat less (though you will still end up dripping in 5 minutes LOL) and excrete less sodium in your sweat, or something like that. The main thing, though is to take it easy at first (with both volume and intensity) to give your body time to adapt AND really figure out what works for you with hydration. I carry fluids (tap water not drinkable in Vietnam) on all runs over 45-50 minutes. You need not only water but electrolyte replacement. Tablets like Nuun or Heed are a godsend. Experiment with the concentration, amounts, and frequency you need--I find every 15 minutes works for me on a run/bike; sometimes I go to 10 minutes if it's a very intense workout or race, in the latter stages of a long run or brick, or if heat/humidity is unusually high. You also need to pay attention to hydration after/between workouts as it's easy to get dehydrated going to/from work, running errands, etc. Maybe S'pre is better as there's more AC and real public transport--here shopping involves walking or sweating on a motorbike. And oh yeah, don't be surprised if you find yourself constantly craving salt, or even chilis!

I find that I have a lot more GI issues (cramps, nausea) while running in this climate, esp. with sweet sports drink, gels, etc. You may have to change nutrition from what you are used to. At least in Singapore you have pretty good access to different choices for hydration/nutrition, lots of convenience shops to top off water, and tap water is probably drinkable in a pinch. Happy trails!