Question about nutrition intake.

I've been using MFP for a while and I love it. I'm an ultra runner and before using MFP, I wasn't hitting my nutrition goals by quite a lot, resulting in headaches and fatigue etc.
I have two more 100 milers this year that I'm training for but I've found the if I run 10 miles or 50 miles in a day, MFP says I need the same amount of sugar, protein, carbs etc. Even if I take a rest day, none of these change. The only one that changes is my calorie intake. Am I doing something wrong?

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