My software says running 5 mph (12 min/mile) burns 541 calories, the same as riding at a moderate 12-14 mph pace.

I find that my stomach is touchier about emptying when I run- so I can't eat large amounts like I can on the bike- I mostly eat gels and Sharkies and maybe just bites of bars, and drink water only. On the bike I can do what ever I want. You can train your stomach to be more accepting of larger "meals" when running by gradually increasing the amount.

I think it's easier to eat while cycling because the heart rate is so much lower.

Nanci