Trigirl- any chance you're eating too many calories? More than about 300/hour and your stomach can't process them and you end up feeling pukey or actually vomiting...
Also, are you getting enough electrolytes? Not enough can cause your stomach to stop working. I aim for 320 with moderate exertion/sweating, 740 mg sodium/hour for heavy sweating. (Any more than that is wasted.) My _first_ sign of not enough electrolytes is vague stomach discomfort.
I the winter, I can eat heavy things like choc milk, sandwiches, etc, but in the summer I subsist on Gatorade and Jelly Bellies, and toward the end, anything salty like chips. At a Century, I just stop at the SAGs and pick out whatever my stomach tells me to- there's no predicting it.
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson