older runner wrote:
japan can be incredibly humid and hot in the summer. like a very hot st louis. it will likely be a race that is slower (doubt anyone will go out at 1:01 or 1:02 half 1/2). this favors kipchoge and rupp. i don't know if rupp has every been in a paced marathon (2017 chicago?). i wish they would get rid of pacers. they are have ruined the sport to some extent. you cannot compare times in a paced race versus a non paced race. rupp's pr could be 2-3 minutes faster or more in a fast paced race.
I'm going to have to disagree on Rupp. His PR is as fast as he can go - in my estimation, that is. He was in a paced 2018 Chicago and didn't get on the podium. If his PR doesn't reflect his ability, why didn't he easily win it? Lack of pacers isn't what has ever slowed him down; to the contrary, he has been able to run close to his limits. He had company late in his PR race. There may have been paid pacers, too (but it was long enough ago that I don't recall).
If it was true that he could run much faster with pacers than without, and he physiologically was capable of 3 minutes faster, wouldn't he have won the fast Chicago race? (Not the impressively slow 2017 race with a very weak field that he did win - see, there were differences other than pacing between the 2 Chicagos). If he could easily break the AR, wouldn't he have done so at a paced race like Berlin? If, as I suspect, he's always wanted the AR and considered it his for the taking, he'd have it by now if he was physically able to get it. He dodges fast and deep races. He ran one - the second time in Chicago - and didn't come close to winning nor taking minutes of his PR.
All that being said, he was and still is fast. Faster than me and anyone on the Board. Just not a secret 2:01 runner who has decided not to run even 2:03.