Quote Originally Posted by matthew View Post
So my question to those who are saying they generally don't eat. My limited understanding of sport science says that the body starts to run out of glycogen stores after 90ish minutes. WHy wouldn't you keep this topped up? What benefit is there to not eating?
A lot depends on how well you are able to use your fat stores as fuel - in theory if you are well enough adapted you have enough fat to fuel you for many hours.
Personally by trial and error, and at a steady endurance training pace (for me around aerobic threshold) I've found a little over 2 hrs to be a reasonable time. I suspect I could go longer but I try to be pre-emptive and start fuelling early rather than bonk at 3hrs plus.