HRE wrote:
In the early 70s Fullerton State had guys doing loads of mileage. Mark Covert, Doug Schmenk and Dave White were reportedly in the 160-180 range. Schmenk and White both had marathons around 2:17 or so. Covert "only" got to 2:22 but was seventh in the '72 OT Marathon. Tom Fleming was a guy who was usually running 150 or better when he was serious. If you go back to the 70s and early 80s you'll find tons of stories like this.
Derek Clayton. Check his book, "running to there top". He did 200 mile weeks, however like most talented runners who ventured into this area he was injured a lot, which shortened his career. Very few people can tolerate the high mileage, 140+ mpw.
Personally I think with the right mix of training, ~100 mpw is plenty for most and perhaps 80-85 mpw is more realistic.