Hey, I'm 23, with pr's of 30:03 for 10k and 14:32 for 5k. After college I wanted to start running marathons, so I got a coach- this old school guy who is really into high mileage, fartleks, racing a lot, and just plain running hard. Well anyways, as I'm getting ready to run a marathon, he wants he to run this one workout next week-says it is a "breakthrough" kind of a workout. It consists of running 1 x mile once an hour for 26 hours straight, all at 4:50 (or better, yeah right). He says it will promote good muscle stimulus and teach me how to run fast without being out of breath but being dog tired. I'm having my doubts about this one, big doubts. Any advice?