The acclimatization conversation has been had many times on this board. Some of it is acclimatization; some of it is your particular body, I believe. I grew up in upstate NY and never, ever dealt well with the heat and humidity. Some people take it better than others. I don't in the least mind riding under 40 degrees. I LOVE riding in the winters here--it's downright invigorating and energizing for me. That doesn't mean I think everyone else should feel that way.

I have gotten much more serious about hydration and electrolytes since starting triathlon. I want to have some gas, so to speak, left for the bike and the run (my weakness). Am working hard on this, so will be interesting to see if it helps.

Malaholic, best wishes for Thursday!