J.R. wrote:
What was your typical weekly schedule?
I saw Jim Zachor win a 50 mile race on the Santa Monica dirt track in just a few seconds off the AR at the time, which was around 5:16. His schedule was 50 miles on Sunday consisting of 7 times around a 7 mile loop, 20 miles Wednesday, and 12 miles the other 5 days. He told me his marathon PR was 2:46, about the pace that he ran for the 50 mile. He ran a really fine race, though I didn't hear of any other results for him.
Typically on weekdays I'd run 20 easy in the morning and 9 at night. 2 days a week the 9 at night would include either 5k of stuff on the track (at about 5x effort) or a 5-6 mile tempo. On the weekend I'd try to do a 30+ mile run each day. Somehow I ended up with no injury or fatigue problems. Most of my runs were at 7-7:15 pace.
I think the current 50 mile AR is 4:51 by a 2:20 or faster marathoner. Before I started this really high mileage stuff, I ran a 2:26 but haven't run one since, so I can't really comment on the improvement other than anecdotally.