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Sunday, October 12, 2008

Chicago 2008: Race Report and splits

Chicago 2008: Evans Cheruiyot and Lidiya Grigoryeva win in fine style

The 2008 Chicago Marathon champions are Evans Cheruiyot and Lidiya Grigoryeva. In two very different races, the Kenyan and Russian triumphed in times of 2:06:25 and 2:27:17, respectively.

For Cheruiyot, it is the first major marathon win of a career that promises to deliver great performances. For Grigoryeva, it's the latest in a series of big wins that includes the Boston Marathon in 2007, Los Angeles and the Paris Marathon.

Below is our report from both races, and splits from the men's race.

Men's race report

The early pace was fast and consistent - sub 3 minute kilometers pretty much from the gun, all the way to halfway, and remarkably, a relatively strong field had been strung out to three by the half-way mark. The temperatures were relatively high - not quite Beijing-like, but then the depth of the field was not the same either. What the commentators failed to mention was that the humidity was quite low in Chicago, which is the big difference from Beijing.

The pace-makers were not up to the job - they were gone within 17 km, and it was Emmanuel Mutai of Kenya, one of the pre-race favourites and a 2:06:15 runner in London earlier this year, driving the pace. The shots from the bike along the route showed very clearly just how aggressive the front running was - it was as though the top Kenyans have all adopted the Sammy Wanjiru-Martin Lel tactics from Beijing - drive as hard as possible at the front, and see who survives!

Evans Cheruiyot was always going to be the biggest danger - the fastest half marathon runner in the field, and we are very firm believers that the short distance speed is THE big predictor of marathon performance. He came third at the world half marathon championships in 2007, running 59:05, and has subsequently run 59-minutes twice, which is a sign of things to come.

The halfway mark was reached in 62:27, which is incredible given that it was being driven by only Mutai, and not the pacemakers. About 25 km into the race, Cheruiyot moved into the lead, running side by side with David Mandago, who was the big surprise package in the race. Mutai was first to go off the back, a gap of 10m created at the 27km mark. That left Cheruiyot and Mandago to slug it out over the final 15km.

The pace was slowing ever so slightly, projecting a finish of 2:05:20 by the 30km mark. The mile pace from 32km to 38km was consistently around 4:50 (or 3:00/km). At 35km, Mandago surged on what must Chicago's steepest hill - a bridge over a highway, and Cheruiyot was momentarily gapped, but held on about 2 strides back. Mandago then surged again, and the gap was 4 strides, Cheruiyot on the ropes but still on his feet.

The knock-out blow did not come, and Cheruiyot was to recover and return to Mandago's shoulder with about 5km to go. Then with 3km to go, Cheruiyot delivered the knock-out blow, opening up a lead of 50m in quick time. Mandago's effort had expired, and it was the faster half-marathon runner who was finally clear and on his way to a relatively unchallenged win over the final 2km. At almost exactly the same time, the women's race saw its decisive move (see report below), which meant that last year's dramatic sprint finishes would not be repeated this year.

Cheruiyot went on to finish in 2:06:25, a huge PB and an "arrival" on the major marathon circuit and surely the start of a great marathon career, given his half marathon credentials. He vindicates the confidence shown in him by the Letsrun.com guys, who picked him to win this race. Second went to Mandago, a great run for him just over one minute back, and third was taken by Timothy Cherigat in 2:11:39.

Below are the splits from the men's race, showing just how aggressive the early pace was, particularly the section from 15km to 20km. However, it also shows the attrition in the second half, where the pace just got slower and slower towards the end.

Women's race

The women's race took on a pretty similar feel to the Beijing Olympic Marathon. The early pace was very slow, projecting a 2:34 time, and the group was understandably large. No one was really forcing the pace, though the Olympic champ Constantina Tomescu Dita was showing at the front quite consistently. She was just there, however, not really doing anything to the pace. The first 10km was super slow, it picked up a little in the next 10 and the halfway mark was reached in 1:16:04.

Just after halfway, the race was suddenly shaken up, just as it was in Beijing, though on this occasion it was not Dita, but two Russians, Lydiya Grigoriyeva and Alevtina Biktimirova, and an Ethiopian, Bezunesh Bekele, the Letsrun.com pick as race winner, hanging on about 3 strides back, who made the move forward.

Then, somewhat surprisingly, Bekele dropped off, which meant that Grigoryeva and Biktimirova, two almost unmentioned runners in the previews, had the streets of Chicago to themselves. Biktimirova was second in Boston earlier this year, beaten in that fantastic sprint with Dire Tune of Ethiopia.

Grigoryeva and Biktimirova are apparently the best of enemies, and live and train in the same town but don't speak to one another. So the race had something of a "personality" to it, and Biktimirova was doing the work out in front, though gesturing to Grigoryeva to give her some assistance. It was very surprising that they were able to create such a large gap so quickly. The rest of a relatively strong field was almost instantly blown away, and I was amazed at how the race was transformed into a two-woman show so rapidly.
Grigoryeva eventually took control, using her pedigreed speed to move into the lead and then open up a large gap at about the 32 km mark. The remainder of the race was something of a procession, the biggest surprise being the size of the time gaps and the relative "ease" of the victory.

For Biktimirova, the final results will have a feel of deja vu about them. In Boston earlier this year, she came second, and the men's race was won by a Cheruiyot - on that occasion, it was Robert Cheruiyot, one of the stars of the marathon running world. Today, the men's race was won by a future star of the marathon world in Evans Cheruiyot.

The weather - last word

It was another relatively warm day in Chicago. Not as bad as last year, but it's not Berlin, that's for sure. The temperatures on the start line were being reported as 60F, or about 16 Celsius, and peaked in the 80s (25 Celsius) by the time the elite men finished. If you're reading that and thinking "big deal", then we're right there with you - it's not that bad. But because of last year's dramatic events in Chicago, and because the public in the USA have been led to believe that marathon running should be easy, everyone was on high alert.

The commentators were very poor regarding the heat - they kept going on about the "very similar conditions" between Beijing and Chicago, when in fact the stats will reveal quite a different picture - Jonathan will provide those in due course. However, the point is that Chicago was SLIGHTLY warm, but most marathons here in SA would give anything for such good race conditions. Same for Kenya, where the conditions in Chicago might be described as perfect for running. There is something wrong with the perceptions of running and the heat in the USA, the "experts" really have no idea about it.

Drink early, drink often, was a mantra repeated many times by the commentators, as though that helps more than just drinking to thirst...you'd have thought these guys were running in the Sahara desert with humidities of the Amazon jungle. Beijing was worse, and Sammy Wanjiru should have made us all sit up and rethink our understanding of how the heat impacts racing strategy after his 2:06:32 win, but alas, more of the same from the "experts"! It didn't affect the elites too badly, however, though the times were perhaps a minute or slower than might have been expected with perfect race conditions.

However, for more detail, there's no one better in the world than Jonathan to comment, since he was right there, in the medical tent, doing a research study specifically to examine the changes in conditions on the course. So our post-race analysis will focus more on that - join us for posts and insights from the tent later in this week!



Anonymous said...

Thanks for the report. Looking forward to the inside story from the medical tent.

Anonymous said...

As someone living in Southeast Asia, I would also give anything to run in those conditions. I must have gotten a different TV commentary since I didn't hear those comments on the air. If they really want to know what heat and humidity feel like, they should run over here.


Anonymous said...

I'm curious now about the humidity. A race report at "letsrun.com" mentioned that the humidity was pretty (according to TV commentators), at 83% at the start, and 61% at the finish, comparable to Beijing.

Unfortunately, I was neither in Chicago, nor Beijing, with a barometer.

Nonetheless, it looks like a new, hot-weather race strategy has emerged, which destroys any competitors foolish enough to follow.

Ross Tucker and Jonathan Dugas said...

Hi Ray, Miguel

Thanks for the comments.

I'm not 100% sure yet of the humidity data from Chicago - haven't heard from Jonathan in the tent. However, mid-way through the race, he did reveal to me that the humidity was not as high as was being reported, courtesy the data he was receiving.

We'll have to wait and see on that, for his post later this week, hopefully. But I'm pretty sure that Beijing (and most races in Southeast Asia!) was both hotter and more humid than Chicago...


Unknown said...

There's data from a weather station near the south end of the course at

There, temperature reached 25 C at 11 am and peaked at about 28. Using the dew point temperature gives RH 70% at 8 am, 42% at 11 and 48% at 1 pm.

I ran in the Melbourne (Australia) marathon yesterday and the temperature here also reached 25 at 11 am (just when I was finishing). No humidity problems, only 25%. However it was the hottest day here for 6 months so lots of people suffered towards the end (me included).

Unknown said...

I ran the Chicago marathon this weekend and the temperatures were fine, there is plenty of shade on the course with the exception of the last 10k where I really felt the heat of the day. The question is, is it really the heat or just simply fatigue that makes the perception of the heat greater?

A Deal Or No Deal said...

Is high humidity even a factor at a temperature of 18 degrees? I've always noticed that on summer days when the temperature is relatively cool (about 18-20 degrees), there is no heat index. According to this site, 18 degrees with 83% humidity makes it feel like 20 degrees. Big deal.

It's not ideal weather for a marathon, and certainly not typical Chicago Marathon weather, but I don't think it makes sense to laud Cheruiyot's run for being excellent "given the conditions". It was worse at London 2007.

Miguel, writing this from Seoul, I agree fully.

Anonymous said...

I ran the Chicago marathon this weekend and I think the weather was tough. I suffered with the heat and humidity and I was finished just after 11am. I live in Texas and trained all Summer in much higher temperatures so I am not sure why I had such a problem but nonetheless it was hard. Obviously there are places with higher temperatures and humidity but the weather was a factor in Chicago this weekend.

Anonymous said...

I am always amazed and the broad and sweeping generalizations that are made by writers. The idea that "the public in the USA have been led to believe that marathon running should be easy" is a little over the top. As for the commentators - While the higher than normal temperatures did not effect the elites much I would wager that the commentators remarks were more geared toward the other ~32,000 people that did not fit into the elite catagory. For those people the advice to stay hydrated was probably well founded given the issues of last year.

A Deal Or No Deal said...

The idea that "the public in the USA have been led to believe that marathon running should be easy" is a little over the top.

It's really not. People run marathons in temperatures hotter than what Chicago had this year or last year all the time. None of them receive mass advisories befitting an approaching Category 5 hurricane.

Ross Tucker and Jonathan Dugas said...

Hi Guys

Thanks for the discussion. I think when Jonathan can produce the weather data, it will become clearer that Chicago wasn't too bad. Really, it wasn't ideal, I'll grant that, and one can expect times to be a little slower than normal, but the reaction of people is way over the top.

And Jason, it's not a generalization - last year's Chicago Marathon was a complete farce, the way it turned into Armageddon when the weather was warm. Every year, we have a 90km race from Durban to Petermaritzburg where it's just as hot, with higher humidities and the race lasts the whole day, right through the peak of the midday. We see FEWER people in the tent than Chicago - only 100 out of 10,000 finishers come to the tent (1%). Chicago's is about 2%, for a marathon.

So I'm afraid I have to disagree, Jason. Conditions in Chicago may not have been ideal, but they were far from difficult. It would be a beautiful day for marathon running in many places...

As for the notion of drinking water and avoiding dehydration, that's a complete myth as well. Check out our "Featured series" tab on the top of this page, and you'll see a series on dehydration. MIght be interesting, but dehydration has little to do with body temperature and overheating. You can drink like a fish and you still won't stay cooler - the main thing that affects body temperature is how fast you run, and for everyone other than the elite runners, they simply don't run fast enough to get too hot...


Anonymous said...

I certainly agree last year’s marathon was a mess, but when you make the statement that the entire general public in one country think a marathon should be easy, I would classify that as a generalization. No doubt there are races and places with worse conditions, I live, train and race in one such place, but it seems like this is turning into a ‘mine is bigger than yours’ discussion. I would also note that it is likely that entrants for an ultra such as the 90km race you mention are likely better conditioned than the majority of the entrants to a marathon. In the end it was a race that was ~20 degrees hotter than would normally be expected. I know if I were the race organizer I would likely do everything to cover myself and it does not seem unreasonable to have some kind of warning system to tell people what they should already know. I agree, the Armageddon of 2007 was ridiculous, but the organizers running out of water was likely a big part of this. Your point regarding drinking water and dehydration would seem to suggest that you should be able to forego water altogether, that is not a myth that I am willing to take a chance on…

Ross Tucker and Jonathan Dugas said...

Hi Jason

Firstly, I didn't make the statement that "the entire general public in one country think a marathon should be easy". I said that the public have been led to believe that the marathon should be easy. There's a massive difference between those two things.

Secondly, the 90km runners are not better conditioned - most are 4 hour marathon runners. Only the faster guys are better conditioned, so the argument doesn't hold. This is certainly not meant to be a "mine is bigger than yours" argument, but it comes across that way because of the messages that you've been exposed to through media re the race and how fragile your physiology is.

Thirdly, no one is criticizing the warning system - I'm not even sure where you got this from. It almost seems you've read a different article.

Fourth, read the dehydration series and then form your opinion. To make the leap to the point where you think you should forgo water altogether is an enormous one, and we've never said that. The series makes clear the approach to fluid, and that would suffice for all the cases last year. People in medical tents in the USA are a completely different scenario to those around the world - your typical medical tent entry is throwing up pure water and Gatorade, it's ridiculous. It's because you all believe so firmly in the myth that you've been fed by Gatorade that you will die if you're dehydrated.


Anonymous said...

Hi Ross,
In response, you are right there is a distinction between the two statements that I did not see before, but I do not think that this is accurate. If attempts have been made to have the public in the US believe that the marathon is easy, which I do not believe there have been, I do not think that the public buy into this idea. I am only going on direct experience with the running community here, it may be different for the non-running community but that seems unlikely.
We will have to disagree on the conditioning aspect of the runners, perhaps they are better conditioned four hour marathoners, or at the very least better prepared, or perhaps know their limits better. Regardless, in my experience ultra runners are by the very virtue of competing in an ultra, more serious and better prepared than marathon runners and usually have a number of marathons under their belts. If you take a step back and read the article AND the ensuing comments you will see the “mine is bigger than yours” argument that I am talking about. This has nothing to do with any media filter; it is a direct result of reading the blog.
My comments regarding the warning system criticism were more geared toward another poster, Adeel, who mentioned ” mass advisories befitting an approaching Category 5 hurricane.”
Regarding hydration, I will obviously defer to your expertise in this area. I am sure many people over-do it regarding water/Gatorade, I have never been in any of the medical tents to see for myself. While it is a leap to say that you should forego water I did not just pull this out of the air, my point here was that the organizers running out of water in 2007 was a big issue yet your comments seem to blow this off by quoting a hotter/longer/more humid race. Again, this is not a message I was exposed to through the media, it is based on your comments.

Anonymous said...

I also ran Chicago on Sunday. I was beyond well-trained for this race, averaging over 70 miles/week the past 4 months, and I certainly expected to beat my 3:07 PR from Boston. The temperature at the beginning was perfect and I started fast, but by mile 12 I was already feeling a bit off and tired. I didn't attribute it to the weather, and I kept pushing through. By mile 19 I was struggling and it had definitely gotten hot. I also ran Chicago in 2007 and I slowed considerably then (finishing in a disappointing 3:27). I told myself the heat was not nearly as bad and slowing down would only keep me out there longer. I was still (barely) maintaining a PR pace through mile 25, when something went terribly wrong with my legs. They wobbled incontrollably and I slowed and did everything I could to keep them under me. This almost worked - I made it through mile 26 and was 100 yards from the finish when they gave out completely. My legs have never failed me before the finish line. I tried to get up and just kept falling down until two fellow runners stopped and pulled me up and pretty much dragged me through the finish (the comraderie of runners - thank you!). My final time was 3:08:59.
Was the heat un-runnable? No. Did it affect performance? Yes. I think it should be pointed out that slowing to account for the heat might make the Chicago marathon perfectly manageable under these conditions, but those of us running our hardest (as is often the case for marathoners who train all year for this one day) are going to feel it. This race was harder for me than last year because of the pace I tried to maintain.

JP said...

Whatever the numbers suggest, I think the time spread between 2nd, 3rd and the subsequent elite finishers indicates that something was in the proverbial air. Under normal/optimal conditions, one does not expect elites with similar pr's to finish so far behind the winner.

My experiences at chicago, both this year and last, suggest that even in moderate heat (like this year) it is impossible to recover once you have red-lined your engine. I would also add that having experienced cramping both years, I have found it interesting that I have recovered much more quickly (which I figure is the result of being prevented from running maximally).

Ross Tucker and Jonathan Dugas said...


Fair points. I'm pasting below the email response I sent to another reader who raised much the same point as you did. I've edited one or two things to tailor it to your specific point:

Fair points, though I disagree about the conditions playing that big a role in the gaps, if you look at Berlin where the weather was pretty much perfect and the gaps similar.

I will say that the weather data that was being measured out on the course revealed a very different picture weather wise. Jonathan has that data and hopefully by about Thursday he'll be able to post some of it - we just have to get permission from the race medical director to release the information in this format. It has implications for race management because the humidity was nowhere near as high as was reported and nor were temperatures. But that's not really anyone's concern - you're only as good as your information allows, I suppose!

I'd argue that you can't know about the heat being the crucial determinant of those gaps given the lack of a "control" - I think it was the pace - a 14:30 5km split from 15 to 20km, off the back of a few 14:40's is ridiculously fast. In fact, if you look at the race analysis, you'll see that they were running close to world record pace up to about 25km. And i did say in my post that the weather was not ideal, not like in Berlin two weeks ago when Geb broke the record.

So I fully agree that the pace was too fast given the conditions, but that's only because the pace was near-world record pace, not because of the conditions, if you follow my logic. If they'd gone through halfway in 63:40, they'd have finished pretty close together, in a time around 2:07, and no one would have noted the 'debilitating heat'. Remember, in Berlin last week, Kwambai blew so badly in the last 5km that he "only" ran 2:06 having been on for 2:04. Similarly, the guy who came third (Kamathi) was in touch for a long way and he finished about 4 minutes down, losing all that time in about 10km. In Chicago, guys let the pace go early and the gaps were similar. So the point is, huge time gaps in Berlin were a function of the pace, not the conditions, and it's a similar thing in Chicago.

More the point for most runners, Chicago was not a bad day for marathon running. A little warm, yes, not suitable for PB's and records, but for most people, the danger of overheating is so far away that it's impossible for them to develop any kind of heat illness. They would have to run 3 minutes a kilometer for this to happen. They're not, they're running 8 or 9 minutes per mile, and the worst that can possibly happen is that they FEEL hot.

Heat stroke is not even a consideration, and nor is "dehydration", which you guys in the USA have been drilled into is a life-threatening condition. Let me ask the following: "how much weight do you think Cheruiyot lost by the time he finished?" I'd guess it was close to 3kg, which is probably about 5% of his body weight. Did he die? Could he have gone even faster if he hadn't lost that weight?

We've weighed thousands of elite and non-elite marathon runners, triathletes, and we know that most people finish about 2 to 3% dehydrated. The elite runners are the most dehydrated of all, because they hardly drink anything. You watch them at water stations and you'll see that they take about 2 or 3 sips (maybe 100ml) every 5 to 10 minutes. That's 600ml per hour, and they sweat 1500ml per hour, give or take. So they get terribly "dehydrated", with no ill effects. There is no danger, only in the minds of the 'consumers' who've been drilled into believing that if they dehydrate, they'll die. The funniest thing is that in the tent, a lot of the people are throwing up pure Gatorade and water! Their problems are caused by drinking TOO MUCH, not too little

No, I'm afraid the myths that the marketing of Gatorade have done on you guys over there have blinded you to the true physiology of fluid and temperature regulation. It's a message that needs to be communiciated....

Just in terms of the heatstroke issue, you might enjoy the following article:


Thanks for the mail!

Ross Tucker and Jonathan Dugas said...

Hi Jason, and thanks for visiting and commenting here.

Just to try to make this point about ultra-runners being better conditioned in South Africa, it is just not true.

I hope that one day you can come out and run Two Oceans or Comrades, because both are incredible events, and when you do, you will see you are surrounded by exactly the same people who run 4-5 h marathons here in the USA. There are plenty of starters of both races whose longest long run was 20-30 km and they limp across the line right before they fire the cut-off gun.

In addition, the last 33% of the Comrades course (maybe more) is littered with people walking or walk/running in an attempt to eke out a finish.

They are no more or less prepared, many are way under-trained and have injuries, and many carry a pouch full of anti-inflammatories to help them cover the distance! Not a practice we encourage, but a reality nonetheless. Ultra-running is very much part of our culture in South Africa, and therefore not all of those who participate classify themselves as "runners" outright. Having said that, however, running is much more pervasive than it is here.

Doing Oceans and Comrades is almost part of your patriotic duty as a South African, and in fact Ross and I have a pact with a few other mates to run Comrades during its 100th year! (Ross, how is the training going man?)

Anyway, your experience of ultra-runners here in the USA is obviously different, but thanks again for sharing your comments.

Kind Regards,

Anonymous said...

Joining this discussion very late. I ran Chicago 2008 as my first marathon and, though I think the heat issue was over dramatized, it seems foolish to not acknowledge the negative effect of heat on marathon performance. Particularly if not acclimatized. I live in a part of the continent where most of my long runs were in 50 to 60 degree weather with little humidity. Did several runs just short of marathon distance at approx 9 min/mi pace, originally planning to run a little faster on race day. Ended up setting my goal at 9:15/mi b/c of heat and struggled to finish at 4hrs 20min (10:00/mi). The on-street thermometers on Michigan Ave in the last few miles (at approx 1PM as it took me over 20 mins to cross start line) were reading 93 deg F. There was very little shade in the last 10 miles. Humidity, thankfully didn't seem that bad. Just b/c some weather station reading is 85 deg doesn't mean that represents the reality in the depths of the concrete jungle. Six wks later I ran a sub-4 marathon in 50 deg F weather despite little additional training in the interim. Weather matters - not sure how you can claim otherwise. Certainly more for the non-elite who are in worse shape and on the course much longer and much later in the day than the 2:0X:XX crowd.