I'm sure this question has been asked before, but I did a search and couldn't find what I was looking for.

My question is related to what you eat before and after, not during per sae (I've got that part down). Do you eat a few more calories the day or two before hand or do you wait until afterwards?

Yesterday I did a 37 mile 3000 foot altitude gain ride and for some reason was shocked to see that I burned more calories than when I did my half marathon. I guess I never really thought about fueling for rides - I just rode (never had a HRM when I trained for my centurys 10 years ago -and I sometimes think that's the way to do it! ). But as I'm going to be riding hilly rides more often than I will run half marathons, I need to start figuring out how to avoid eating too much or too little. Any suggestions are welcome.