My longest regular commute was 18 miles one way. Since I inevitably left late, it was an all out time trial going to work. I forget what I ate before I left but it couldn't have been heavy. I'd usually eat a bar of some sort while I was riding (very "euro"). On the way back my ride was much more leisurely. I gained a lot of weight at this job, mainly due to the gym (went from benching 90 lbs to 200 lbs).

Another somewhat regular commute was about 15 miles, to the shop. I'd meet up with a coworker/teammate (actually he'd ride to my house). We team time trialed together to the shop. He shelled me on some of the hills but otherwise we'd work really hard together. He won the Cat 4 Bethel Series, I won the 3-4s, and this was while the guys at the shop spent the evenings after work (7P to 1 or 2A) building up a new shop space. I was in my "poor bike shop owner" mode and basically got free food from the bagel place. So danishes, croissants, bagels. My diet consisted of stuff they were getting rid of in the evening.