I asked this same question on the 50+ forum. I like to expose my problem to a wider audience, please.

I did an intense six hour bike workout with a lot of sweating at elevated HR of 120 to 140.
I had a very large high Carb breakfast.
I drank one large bottle of water per half hour.
I ate half of one energy bar every half hour.
I ate two sandwich with honey and peanut butter.

The exercise routine was successful.

Five hours later I woke up vomiting and IG distress.
Someone said I was lacking electrolytes. I thought the energy bars took care of that.
It also could be a flu bug.
I appreciate your comments.