A friend of mine suggested to check this one out. Been a while but sure is interesting as ever…
If you are asking a "Lydiard" question, he believed a long run of 2-hour or more is absolutely important (with a good reason). His original runners DID do some runs longer than 3-hour at times and there's nothing wrong with it. Now-a-Coach; yes, we would cap the long run at 3-hour. The comment about longer than 3-hours being detrimental is actually from Dr. Jack Daniels but we felt that's about right. Of course, you can't generalize it and say; Toshihiko Seko was "wrong" because he did a 50-mile run.
Over all, Arthur liked his runners do a long run of 2:00-2:45 once a week, usually around a hilly Waiatarua 22-mile circuit. They would run it pretty hard during Conditioning (odd 2:10-2:15) and much slower once they moved on to Hills and Track Training (2:40-ish). But that was simply because they were running that particular loop. As HRE talked about, Arthur moved on from there to recommend time-based training more than mileage-based. This is because when he went on and started coaching people he couldn't be with. They were doing 100-mile-a-week so much slower and he found that's TOO MUCH; which, interestingly, we found so many people doing right now--too much running and doing them more harm than good.
"Running to the Top" was written during a rather interesting period. I had talked about this with Arthur but, even though he started the original jogging group in Auckland back in 1960s, he didn't know what to get about those who don't want to do a lot of running yet wanting to run a marathon. The era of professional people suggesting people that anything more than 40-miles-a-week can harm you, possibly kill you, is a foreign world to him. He had his original joggers (ages between 50-72) training 7-days-a-week and many of them went on a completed a full marathon "somewhere around 4-hours". Things had changed so much since--when you look at Runner's World back in 1970s, you see people posting, saying: "I'm a hobby jogger with a 3-hour marathon PR…" Now dipping under 4:00 is a feather in a hat!
What he was talking about in that particular paragraph is:
Do 3 long runs a week with one of them being 2:00-2:30. Every 4 to 5 weeks, get that long run progressively longer to get to your expected marathon DURATION. So, if you must have a numbered example, it would look like:
2:00-2:30 (with other 90+ minutes long runs during the week)
2:00-2:30
2:00-2:30
3:00
2:00-2:30
2:00-2:30
2:00-2:30
3:30
2:00-2:30
2:00-2:30
2:00-2:30
4:00
Taper (3-4 weeks)
Something like that.
Even for a beginning marathon runner, he would have still preferred to give hills and intervals and tempo runs to get them ready for a marathon because it involved a lot more than just doing long runs to get you ready to run well at any distance even a marathon. However, the problem is, and this is something I had discussed with him in 1997 when he told me about this new book of his and more in depth in 1999 when he came to the US for his second to the last US tour, majority of "marathon participants" don't give a damn about "racing" a marathon. They just want to finish. This is a big dilemma because, with Arthur's original peaking, the longest run of the entire program would come in somewhere around 14-16 weeks out from THE race. For someone training for a 4:30 marathon, this could mean you'd be doing "only" 13 or 14 miles 3 months out from the actual marathon!! Psychologically, that's a bit scary! So for someone like that, you can do a plan such as above, and I'm not sure if Arthur would have actually recommended a plan like that without hills and other parts of his program and publish it (I highly doubt it…), and it would work just fine.
In Dr. Daniels' words, "…stress is a function of time spent doing something…" Arthur certainly would have agreed that someone pounding 4 or 5 hours week in week out, trying to fulfilling "three-20-milers" regime of a marathon plan was actually doing more harm than good. It certainly was interesting to see a man who spent decades encouraging people to "run more" to have to tell them not to do too much!!