Originally Posted by
thompsw
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The other thing is that your 700 calories pre ride cannot possibly be digested before you start riding. Your body needs about 1 hour to digest 250-350 calories, so that food is simply sitting in your stomach and then joined by other solid and liquid intake during the ride. If you are going to eat that much pre-ride, do so 2 hours beforehand.
With due deference to your long-distance accomplishments, and admitting that I have only ever done five centuries (all of them this year), I don't think the above caution holds for all of us.
For any ride over 70 miles or so, and I know I'll be flamed for admitting this, I stop by McDonald's on the way to the ride start and have, at the least, an Egg McMuffin, a potato cake, a cup of coffee and some of those decadent sugary gooey little cinnamon roll thingies, usually not more than 45 minutes before the ride starts.
For a long effort, my body WANTS that kind of food (sugars, fats, protein, carbs)- maybe due to a background in construction, where a big breakfast fuels the fires for hard work.
I'm sure it's not for everyone, but I can tell you that, in my case at least, it's not "simply sitting in your stomach"- it's being turned into miles!