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Comparing Kazami and Walmsley's Runs


American Jim Walmsley gave the men's world record set two and a half years ago by Japan's Nao Kazami a serious scare this weekend at the Project Carbon X 2 100 km. A quick look at their splits shows two different race strategies, Kazami essentially going out hard and slowing the second half and Walmsley running the first half more conservatively and then trying to negative split. Both had relatively slow starts before zeroing in on their first half target pace, Kazami settling in around 36:20 per 10 km and Walmsley around 36:50 until they hit halfway. At that point Kazami was projecting a 6:04:10 world record, with Walmsley's 50 km split projecting to a record of 6:08:30.

From there they swapped, Kazami going 36:52 from 50 km to 60 km and Walmsley 36:22. That proved Walmsley's fastest split of the day, as although he stayed close to that pace through 80 km  he began to slow for every remaining 10 km split until the finish. In Kazami's case he hit a rough patch between 60 and 70 km, slowing to 37:46 before turning it back around and running faster for each of the next two 10 km splits. The difference in their paces between 60 km and 80 meant Walmsley went ahead of Kazami for the first time at 80 km, at which point he was up 35 seconds, but with the difference in their pace trajectories Walmsley dropped back to just 3 seconds ahead at 90 km.

Kazami had slowed 46 seconds over the final 10 km of his world record, running his slowest split of 37:55. This meant Walmsley had to run 37:57 for his final 10 km to beat Kazami's mark, slower than any of his splits up to that point. That might have seemed doable, but having slowed from 36:33 to 37:41 for his previous two 10 km splits, the latter his slowest of the race, it was a bigger task than in sounded and proved out of range. Walmsley closed in 38:10, like Kazami's closing split his slowest of the race, bringing him in a painful 12 seconds behind Kazami's mark and another second off a new record. 

To put in terms of a marathon, Walmsley ran the first half on WR pace, sped up, started to fall off pace coming up to 35 km, and couldn't hold it together in the final 4~5 km. Not exactly a surprise. With a little more conservative early second half he might have been able to hold it together better over the last 20 km, but we'll leave it to the ultra experts to talk about what he might have done differently or might do next time. In any case it was a great effort that came close, and hopefully there's more where that came from.

© 2021 Brett Larner, all rights reserved

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Comments

Anonymous said…
Valiant efforts by Walmsley yesterday and he came so close! I appreciated that it was broadcasted live on Youtube for free which seems to be rare nowadays (in the US at least). Do you have any data on the conditions of the 2018 Lake Saroma 100k? I heard there was some favorable wind aiding the runners that day on the point to point course. The conditions yesterday in Arizona were near perfect too in terms of the weather but it was on a rather boring loop course.
Brett Larner said…
A great run from Jim to be sure. However, Lake Saroma meets World Athletics course regulations for world record eligibility and as such is not defined as a point-to-point course. It seems that there are people within the ultra world who present it otherwise, but whether they're unaware of the rules or have other motivations for ignoring the rules in order to make false claims isn't something I could speculate on. I have the feeling they're confusing a disagreement about the way the rules are written with whether something meets them, but in any case it's as false to say a record-eligible course is point-to-point as it would be to say the opposite.
Brett Larner said…
I've had a dozen or so comments from people who insist on saying Lake Saroma is a point-to-point or wind-aided course. I know the last few years have made it difficult to differentiate between facts, opinions and false statements, but here's how they would apply here:

Fact: Terms like "record-eligible" and "point-to-point" in the context of road racing have specific meanings as defined in World Athletics rules and regulations. These are mutually exclusive categories. You can look these definitions up in the rules and regulations freely available on the World Athletics site.

Fact: Under the definitions above, point-to-point courses are not record-eligible due to the possibility of excessive wind assistance, while record-eligible courses by definition do not have excessive wind assistance.

Fact: Lake Saroma meets the criteria for record-eligible as defined in World Athletics rules and regulations.

Opinion: The World Athletics rules and regulations regarding the definitions of "record-eligible" and "point-to-point" are too lenient.

False statement: Nao Kazami's world record run on the Lake Saroma course was excessively wind-assisted.

The false statement above and variations people have posted in comments and elsewhere are based on considering the opinion above to be more valid than the facts. This does not, however, make it a true statement. In order to become a true statement, one of two things would have to happen:

1. The false statement would have to be changed to recognize the validity of facts over opinion.
2. The facts would have to be changed to match the opinion, i.e. you would have to successfully lobby World Athletics to change the rules and regulations on this point.

I'm certainly not opposed to point #2, but until that happens false statements denigrating someone's achievement shouldn't be propagated. I realize there's a lot of it going around these days in some places, but just because you don't like the outcome of the system that's in place doesn't mean you can just pretend it's not real.

Hope this was helpful.
Anonymous said…
Thanks for clarifying, Brett!

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