When and where is the event? Lots of cold fluids if it's hot, hots of warm comfort food if it's cold.
I've finished a few rides in serious "bonk". Some of your longer route riders may experience that. When bonk happens, I don't care what the food looks like, I gobble everything in sight as quickly as I can.
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My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.