How many calories does one burn during the RAO?

Photo courtesyHonza Groh

Sometimes when I talk about doing long rides people ask me, "How many calories do you burn on a ride like that?" Since it's incredibly hard to measure something like that, let's do a little math to estimate.

First some assumptions
1) Assume an average of 14 mph. (This is optimistic)
2) It is known that vigorous cycling burns ~700-900 calories/hour. Since vigorous cycling is what you want to avoid during really long races, let's assume I'll burn 500 calories/hour.

Knowns
The race is 540 miles long.

Now for a little math.
We divide the rate into the distance to get the total time. 540mi./14mph=38.6hours
Then we multiply the time by the calorie rate to give total calories. 38.6h*500cal/h=19285cal

Wow, about 19000 calories! That's equivalent to roughly nine days worth of food. Now you know!