Wesley Korir and Sharon Cherop have won the 2012 Boston Marathon for Kenya. Surprise names, perhaps (particularly Korir), but you might, at first glance, call it “just another Kenyan victory”. It was anything but. Today was a reminder of the difficulty of the marathon, because Mother Nature, so kind to Boston one year ago, decided to strike back and show the other extreme of marathon running. The winning times – 2:12:40 for Korir and 2:31:50 for Cherop, are a staggering 9:38 and 9:14 slower than last year’s winning times respectively. That’s almost 19 minutes, collectively, and we were today reminded that even the great runners are “mortals” in the face of tough conditions.
The timing from Boston tells of three races, and it’s too tempting not to compare. There was Geoffrey Mutai of 2011 – the astonishing 2:03:02 performanced, aided by a strong following wind and ideal temperatures of around 50F. Then in 2012, there were Wesley Korir and Levy Matebo, who finished first and second, but ran two quite different races, and their paces tell the story of the day.
So here are three thoughts about Boston 2012, including some insight on the physiology of the various “meltdowns” we saw today, and how Wesley Korir and Jason Hartmann got it just right:
1. Caution counts when conditions make the margin for error smaller
We are so used to seeing aggressive racing by the Kenyans. Surges and brutal accelerations have given them countless titles, in addition to super fast times. Today in Boston, with the mercury rising above 80F and in bright sunshine, fast times were never going to happen, but the racing surges in the second half were going to decide the title.
And sure enough, in both races, the early pace was super slow. The women went through 15km in 55:15 – that’s a full 5:06 slower than the 2011 equivalent. The men hit 15km in 46:48, which was 3:03 slower than in 2011. So the first half was conservative, as one might have predicted (though even I was surprised at how conservative it was). The women’s projected time was 2:35 until late racing brought it down, whereas the men didn’t dip below 2:11 from the 10km mark onwards.
Shortly after halfway, the attacks began, particularly on the men’s side. Matthew Kisorio went off the front just after 25km, and Matebo and Geoffrey Mutai followed. A few small attacks followed, the field regrouped and then split again, and it was Matebo, Kisorio and Mutai once again at the front. Then Mutai dropped back, and fell precipitously off the pace – having been in the lead pack at 27km, he was 1:22 down at 30km and it was clear that his race was run. He dropped out shortly afterwards, and the talk is that he was suffering from cramps.
Then it was Kisorio’s turn to crack. He led at 30km, was the aggressor responsible for the early attacks, but shortly before 35km, he began to drop off the pace (10 seconds down). From 35km to 40km, he absolutely blew, running that 5km stretch in 19:06, before eventually finishing in 10th with a final 2.2km of 10:13 (4:39/km pace)!
So that left Matebo, who had also mixed it among those surging at 25km. He held out longer, but his time was also coming. Having built a handy lead at 35 km (10 sec to Kisorio who was going backwards, and 57 seconds to third place, he ‘melted’ between 35km and 40km, covering this stretch in 16:40! The result was that he was reeled in by Korir, who would eventually pass him for the win. To his credit, Matebo hung on, even counter-surging at 40km when caught, but it was to no avail for the win, but he did hold onto second place.
And then there was Wesley Korir. He did not get involved in the surges, but ran a very solid and constant pace. He was the benefactor of his patience, because when the three ahead of him were blowing and bailing and slowing dramatically, he was able to pick them off by running pretty much the same pace the whole way. It was a lesson in even pace, and it highlights the risk of the aggressive surging strategy that the Kenyans adopt.
The problem, physiologically, is that these surges are metabolically costly. And therefore, they are also very challenging from a thermoregulation point of view. Repeated sprints, for example, are one of the best ways to drive your body temperature higher, and while these men were not exactly sprinting over and over in the marathon, the mid-race surges do more or less produce this result – body temperature climbs and perhaps more importantly, thermal comfort and perception are hugely affected.
Now, on a “normal” day, this is not a huge problem – body temperature and thermoregulation are not crucial factors, and the world’s best are able to recover quickly from the metabolical cost of the surge. The physiology of thermoregulation is different – you can’t just suddenly lose heat, and so the cost of the higher intensity is paid out over longer periods, taking much longer to recover from. As a result, the line between “just right” and too fast is extremely narrow, and a typical attack is now the one that breaks the aggressor and not just the rest of the field. Therefore, success comes to those who avoid the variations in pace and the harder efforts, and that’s what Boston showed today.
Take a look at the graph below – I spoke earlier of three races. We compare the 2011 Mutai performance (blue line), the race run by Levy Matebo (red line) and the winning performance from today of Wesley Korir (green line).
The circles at the bottom show just how far off last year’s pace the race was at each 5km interval – 54s down at 5km, another minute lost to 10km, and so forth. By 25km, for example, this year’s race was almost 5 minutes slower than Mutai’s last year. Then came the “surge” from Kisorio and Matebo, between 25km and 30km. That surge led to the only 5km split of the 2012 race that was faster than 2011 – 14:59 for Matebo vs 15:07 for Mutai last year (the green circle, – 8 seconds).
But notice Korir’s pace line in green – he didn’t respond to that increase in pace. He held his pace at between 3:05 and 3:10/km, much as it had been for the entire race, and lost contact, falling to sixth overall. That continued to 35km, where he conceded another 18 seconds, but was now up to third as those who had been sucked into the attacks paid for it. Then, from 35km, he started to reel them back. His split from 35km to 40km was 15:44, and while that’s not fast in absolute terms, it was the fastest of the race for that segment. Meanwhile, Matebo was exploding up ahead, running the same stretch in 16:40, and the two were together at 40km.
Not surprisingly, Korir had more in reserve, and closed the final 2.2km in 7:13. That too was the fastest of the race, whereas Matebo finished with a 7:39.
On the women’s side, the pace barely deviated. It began slowly at 3:46/km, and while it got faster, it was a race mostly lacking in real attack. Sharon Cherop was aggressive at the front, but it was a grinding win, and she just ran everyone off systematically, until she made one final, decisive move with 800m to go. It would be terrific to see 1 km splits (normalised for the hilly profile), to see whether the men’s race was more variable (I suspect it was considerably so).
The moral of the story is that on a hot day, the even paced approach works and is vital, and today, the Kenyan strategy of attacking and surging was very costly indeed. One final illustration – Jason Hartmann of the USA, who had a great race to finish fourth. He took the “Korir approach” of not responding to the attacks at 25km. The result was that he actually dropped out of the top 10 at 25km, but then began to claw his way back up, by virtue of some really even pacing. His 5km splits from 25 km to the finish were: 16:03 – 16:13 – 16:22, with a final stretch of 7:30 (second fastest in the race). Remember, this came at a time when those early leaders were running 16:40 (Matebo), 18:01 (David Barmasai), and even 19:06 (Kisorio)!
The heat makes it good to be something or a tortoise! Or at the very least, an even paced hare!
2. Conditions really matter. And Boston today was brutally, $%&#ing hard
There was a lot of talk about the temperature before the race, many people panicking about the imminent death and danger the runners would face. I think it’s largely overhyped in terms of safety, but today did illustrate just how important conditions are for fast racing and performance. Today’s races were 7.8% (men) and 7.0% (women) slower than last year, and that’s partly the heat, partly the lack of wind, but it goes to show how “fragile” performance is when you’re trying to race for 2:05 or faster.
That’s why talk of a sub-2 is so premature. Even if the athletes are in ideal physical condition, it needs environmental factors to be absolutely perfect to allow it. And this idea that these African athletes are so special that they can just break down the physiological barriers is a fairytale. They’re exceptional, make no mistake, but barriers are real and if conditions are not perfect, no “belief” or lack of limitation overcome sub-optimal conditions.
Back to Boston – today we saw a day when a mid-race attack at 3:00/km was enough to create gaps of over a minute within 5km! It was a day where running at 15:30 per 5km pace was splitting a world class field full of 2:06 men. That’s a brutal day. And while it wasn’t that hot, I think one can’t overstate the impact that direct sunlight has on thermal load and challenge.
Recently, when I was putting myself through my little barefoot Kilimanjaro experiment, it became clear that direct sunlight exerts an effect on temperature and thermal comfort that is far greater than we acknowledge. The only reason I was able to summit Kilimanjaro barefoot in air temperatures below freezing point was because the African sun did a magic job heating the ground up. At one point, at 4,700m altitude, the air temperature was -3 degrees celsius, and the ground was 20 degrees celsius!
Now the opposite implication was true for Boston today. Temperatures in the shade were reported at around 82F, but in the sunlight, which is most of the race, they would have been 10 to 15 degrees higher. The result is an effective temperature closer to 95F, and that’s the difference between today in Boston and Beijing 2008. There, Sammy Wanjiru apparently defied physiology and physics to run 2:06:32 in the heat and humidity (I say ‘apparently’ because that kind of performance does not defy anything – you can model it as entirely possible given his mass and the pace). But it was, I believe, cloudy, and I think that’s a crucial difference, especially in a city surrounded by buildings.
So Boston 2012 provided all the elements of a war of attrition, and 2:12 and 2:31 winning times for men who run under 2:06 and women who run 2:22 is evidence of it. It doesn’t make for the same kind of awe as we had one year ago, but perhaps it’s a much needed reminder of just how remarkable a 2:05 marathon is, now that it seems so “common-place”!
3. Kenya have bigger selection problems after this weekend
Final point, a short one. What would you do as a Kenyan selector after this weekend? You’ve seen the Ethiopians respond to your amazing 2011 by producing five sub-2:05 performances in 2012 so far. They occupy five of the top six spots in the world rankings, and have beaten one of your stars in Rotterdam.
Another one of your champions, perhaps the best of them, has failed to finish a race in Boston, and while it’s a freakish race because of the heat and you can take some consolation that at least other Kenyans dominated, you now have a major dilemma on your hands! Do you pick Mutai, 2011’s best racing marathon runner by virtue of wins in unpaced Boston and New York? Do you write Boston off as a “bad day”, an anomaly? Because if you do that, then Mosop’s 2:05:02 in Rotterdam may also be a “bad day”…
And what happens in London may complicate life further. If that’s an ideal day, and four or five Kenyans break 2:05, then a difficult decision becomes almost insoluble! Time to draw straws!
Personally, I’d pick Mutai, because 2 out of 3 race wins, and the manner of those wins in 2011 mean that his pedigree is unquestioned. Plus there is his cross-country pedigree, and Boston 2012, much like Boston 2011, may be races to write off as once-in-a-lifetimes…
Oh, and finally, spare a thought for Michel Butter of The Netherlands. He was using Boston to try to qualify for the Dutch Olympic team. His requirement was either to run 2:10, or finish in the top 8 with a 2:12 or faster. He ran 2:16:38 for 7th. So he got the place, but missed the time, and hence the Olympic spot. That’s a bitter pill to swallow, because as I mentioned earlier, the elite men were 7.8% slower than last year’s times, and about 5% slower than their typical race times. Butter missed the target time by 5.1% (the 2:12 standard). Bearing this mind, and that Boston is typically a slower course than the flat races of Rotterdam, London, Berlin etc, I would use discretion and pick him anyway…
And then to anyone else hoping that Boston would help them to a PB or selection, 2013 is another year. Perhaps Nature will be kinder again! I’d say that she owes Boston a good day, but then again, this may have been payback for 2011!
Finally, if you missed it, and want to follow my “blow by blow”, “meltdown by meltdown” coverage of the race on Twitter, check it out here.
I’ll do the same thing for London on Sunday – live updates and splits throughout the race, so join us on Twitter if you haven’t already done so!
This post is part of the thread: Marathon Analysis – an ongoing story on this site. View the thread timeline for more context on this post.