Mimi, there are plenty of powders and capsules out there that provide the electrolytes only without any calories. You can easily over do the calories on really hot days requiring lots of liquid and electrolytes but not a lot of calories.
Frends know gud humors when dey is hear it. ~ Da Crockydiles of ZZE.
Ideally, if you're getting the right amount of fluids, you'll weigh the same before and after. So 12lbs lost is obviously bad, but 6lbs gained isn't doing you any good either. You most definitely are not eating enough. For 4.5 hrs out on the bike you need waaay more calories than a bowl of cereal and a Gu, especially because of your stats. I've had some heat exhaustion symptoms when I'm pretty well hydrated just because I desperately need more food.
I struggle to take in solid food when it is really hot. I think someone mentioned using ice - I know SK had ice on her neck at Wildflower and I filled my sports bra with ice at every rest stop on DMD last Saturday. Reducing the core temperature really helps.
In terms of fluids, as it does get hotter, I tend to go more for the plain water and endurolye combination. Also V8 (the elixir of life). These things seem easier on my stomach than sports drinks. However, when temperatures are moderate I get a lot of calories from sports drinks. I think you just have to experiment and see what works at different temperatures and in different situations - it does sound, Amy, like you've had some improvement over your symptoms from last year. So that's good, right?
I had a wicked headache all morning Sunday after DMD. I drank a LOT of water Sunday and it gradually went away. I don't know if it was dehydration, but I suspect it was. There was just no way not to get behind in that ride.
We had a guy on our Death Ride team this year who suffered from heat exhaustion type symptoms. (He had to drop off the team unfortunately because he really was not well and I honestly think there was more to his issue than heat exhaustion.) But anyway, he did say something about his doctors telling him that once you have heat exhaustion "episodes" you are more likely to have this issue in the future. I don't know if it is true or not, it's just what he relayed.
Sarah
When it's easy, ride hard; when it's hard, ride easy.
2011 Volagi Liscio
2010 Pegoretti Love #3 "Manovelo"
2011 Mercian Vincitore Special
2003 Eddy Merckx Team SC - stolen
2001 Colnago Ovalmaster Stars and Stripes
We also had a guy on the team once who had 3d degree burn scars over much of his body - he couldn't sweat and had a VERY hard time in the heat. He also ended up not being able to ride. Pretty wild.
Sarah
When it's easy, ride hard; when it's hard, ride easy.
2011 Volagi Liscio
2010 Pegoretti Love #3 "Manovelo"
2011 Mercian Vincitore Special
2003 Eddy Merckx Team SC - stolen
2001 Colnago Ovalmaster Stars and Stripes