pr100 wrote:
I reckon it's perfectly possible if you're willing to put in the training. Especially if you're relatively slim.
Wouldn't it be the other way around?
He said ran a half marathon at 11 minute pace, so that's something like 2:20 - 2:25. Before he can run sub 3:00, he has to be able to run something like sub 1:25 in a half.
So we would want to know why that HM took over 2:20 - other than only running 20 miles a week - before we predict that he could cut an hour off that time. He also didn't say why he only ran 20 miles a week - if it was due to injury problems, that could be a limiting factor.
Now if he was carrying a lot of extra weight when he ran that HM at 11 minute pace, that is one area where there is potential for significant improvement... he can lose a lot of weight in 5 years.
But if he was already reasonably slim when he ran that HM, I'd think there would be less chance of him reaching that goal.