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Thursday, June 16, 2011

30km World Record: Does it bring the 2:02 Marathon any nearer?

Does 1:26:47 for 30 km = 2:02 over 42 km?

Given the slew of comments and discussion on the whole barefoot running issue, we thought we would move to another controversial (and recurring) topic:  The 2:02 marathon.   If you missed the debate on barefoot running, we really encourage you to read the post and the comments, because dare we say that together they represent some of the best discussion on the topic anywhere.

But as we try to leave that topic behind (for now - Prof Daniel Lieberman has just been confirmed as a speaker at the UKSEM conference in November, along with Ross, so more to come.  Also, more on this conference soon!), let's move on to marathon running once again, and specifically Moses Mosop's world records at 30 km and 25 km at the Prefontaine meet in Oregon on 3 June.

The what record?

Yes, you could be forgiven for taking a second look at that, because the both 25 km and 30 km are hardly ever contested, falling outside the "traditional" 5, 10, 21.1, and 42.2 km distances.  But there is even a record for 50 km, incidentally set by Thompson Magawana en route to a Two Oceans 56 km marathon course record in 1988.  These more obscure distances are on occasions contested, and this was the case a few weeks ago in Oregon at the Pre meet.  It was a special event on the Friday night, and the last time we can recall one of these obscure records being challenged was back in January 2009 when Josh Cox tried to break the 50 km record by continuing past the finish line of the Rock 'n' Roll Marathon in Phoenix that year (he fell eight seconds short, by the way!)

Mosop debuted at Boston this year and lost to Mutai by only four seconds---2:03:06 compared to Mutai's 2:03:02.  So he burst on the scene with the fastest debut, and with a time almost a minute faster than the world record in a race that garnered heaps of controversy as the Boston course is not certified due to the point to point nature and elevation drop.  Our readers will recall plenty of discussion about that back in April, and you can check that here if you missed it - in the end, it was the wind that drove the times as fast as they were, not the course profile, but the times won't stand because of the profile.  For his efforts there he will be partly remembered but probably mostly forgotten, because who among you can recall the 2nd place finisher (and pacer) in Berlin 2003 when Paul Tergat ran 2:04:55 and won by only one second?

The marathon debutante:  Full of potential but bound to bust

What he demonstrated at Boston was that, at least for the moment, he must be taken seriously as a candidate to break Geb's current marathon record of 2:03:59.  Fast debuts are a funny thing, because immediately people peg the runner as a serious contender going forward, but they often fail to replicate their amazing first-time performance.  Until 3 June Mosop was in that category, but after his 30 km record, which was pretty much a solo attempt, he ups the ante and has shown that he has good form and potential.  Thirty km is not 42.2 km, however, and he still must prove himself in a Big City marathon this Fall or next Spring if he is to maintain his status as a potential record breaker.  But let's take a look at his 30 km record run and peer into The Science of Sport crystal ball for now!

The ever-important negative split

Below you will see a graph of Mosop's 15 km splits in the attempt, and the most notable aspect is that it was a huge negative split.  He hit 15 km in 43:54 and then went 61 s faster for the second half.  We have written about it plenty here, most recently about the 800 m distance.  That race is unique, but in longer races an even or negative split is optimal.  That is based on an analysis Ross did as part of his PhD that looked at the pacing strategies over various track distances, and found that the fastest performances over events 1500m or longer are almost always run at even paced with an "end spurt" in the final kilometer.  

In fact, out of 67 world records over 5,000 and 10,000m, only ONCE has the fastest kilometer of the race NOT been either the first or final kilometer - it is remarkably uniform that at the top level, at the limits of performance, you start quickly, settle down, then speed up at the end.  The result is an overall even pace and a U-shaped curve.  The granularity of the one km splits is farther down, but here we see his 15 km split:

To provide a comparison, Geb ran a near even split from 21 km to 42 km in his record in Berlin - he passed the 21 km mark in 1:01:48 and then hit 42 km in 2:03:27.  So a one minute negative split even over 30 km is quite a big one, and suggests that Mosop possibly could go a bit faster by adopting a more even pacing strategy.

Is 2:02 possible?  You decide!

What we did next was look at his km splits as recorded by his coach Renato Canova and posted in the LetsRun.com forum.  We then drew some lines on the graph to show the pace for the current marathon record (2:03:59, black), 2:03 pace (blue), and 2:02 pace (green), to show you where he was relative to those speeds during is 30 km attempt.  

It's pretty striking, actually, and at the very least shows Mosop's form right now.  But we all know that form can be a precarious thing and very transient.  It would be amazing if Mosop can produce this kind of form in which ever Fall marathon he chooses (Moses, if you are reading, we hear Chicago is nice in October!), but we would not be at all surprised if he cannot reproduce this level of performance.

But if you check the graph here of his one km splits, it's telling.  Yes, we know that 30 km is not 42.2 km, but perhaps most telling is his huge surge around 18 km, where he put in two very fast splits of 2:45 for the 18th and 2:46 for the 19th km.  The telling part is that he did not appear to pay for that later because he maintained a faster pace from there until the end, when he clocked a 2:47 for his last km. 

Again, we understand fully that 30 km is not 42.2 km, but taken together with his performance in Boston back in April this record has meaning.  We can't say for sure if it translates into a 2:02:xx marathon time, but until Mosop's next race it places him firmly in the pool of contenders.  Given the wind in Boston we might call his and Mutai's performances there flukes or outliers, because remember nearly everyone ran faster than "normal" and many set personal best times.  And it is possible that Mosop's performance there gave him the confidence to run at these paces, but again he will need to prove himself at this next level in a Fall and/or Spring race.

So Mr. Mosop, we now look to you and Geoffrey Mutai as the two most likely candidates to break the world record, especially given the untimely death of Sammy Wanjiru.  For now, as fans all of can wait with anticipation for the Fall marathons.  It's a big ask---it always is, breaking a record, especially one with such small margins for error as the marathon record.  But he should take confidence in this performance on the back his Boston race.  Given the right conditions, course, and pacers, on paper now he has a chance at besting 2:03:59, although going sub-2:03 might be out of reach for now.

On the horizon

Meanwhile it is nearly Tour de France time, and we are excited to see what the race will bring.  Controversy is on the list of deliverables, but there is likely to be good racing, too, and you can expect our regular analysis and commentary in July.  And let's not forget that the IAAF World Championships are in August.  There is plenty to talk about with Caster Semenya and also the regular analysis of who is and who is not on target for their Olympic campaigns for London 2012!