A 2:03:02. 3 to 4 min? What effect did the wind have?

2:03:02 dissected.  What effect did the tailwind have? 3 to 4 minutes...?

I don't know the answer to that question.  Let me say that right upfront.  It's insoluble.  But it's too intriguing not to ask, and attempt to answer, and there are a few approaches to it to shed light on a  quite remarkable Boston Marathon, now that the wind has died down and the dust settled on the fastest two marathons in history. Just where do Geoffrey Mutai's 2:03:02 (and, for that matter, Moses Mosop's 2:03:06) rank in the history of marathon performances?

Not a recognized record - why not?

As you'll know, Mutai's record will not be accepted as the official world record.  The main reason is that Boston is a point-to-point course with an overall drop in elevation greater than 1 m per kilometer, a one in a thousand drop (Boston drops by 135 m).  Also, a second criteria for course eligibility is that "The start and finish points of a course, measured along a theoretical straight line between them, shall not be further apart than 50% of the race distance".  This would apply to Boston, because the course is basically a straight line running north-east, and that is why a south-westerly wind, as we saw today, would have such a profound effect.  The image below (click to enlarge), again taken from Letsrun.com in their preview, shows this nicely.  The wunderground.com site had the wind at 14mph westerly, incidentally.

So not recognizing Mutai's time is indirectly influenced by the wind (as indicated by that second clause which would help to prevent a 'wind-aided' record), but it's mainly because of the drop, despite the fact that Boston is actually a slower course than the other Majors, as we'll see below.  But the real meat of this debate is the effect of the wind on the times?  And what would Mutai have run on any other course?

Let's repeat that this question is unanswerable.  We will never know exactly what Mutai would be capable of on a flat, fast course like Berlin or Rotterdam on a still day.  We will never be able to quantify the improvement that might have occurred thanks to the tailwind during today's race.

Equally, we will never know how much Boston's relatively tougher profile, with its Newton Hills in the second half, costs runners compared to the flat and fast courses in Europe and Chicago.  So to ask "What could Mutai have run in Berlin?" is a rather futile exercise.  I know this, and so this is somewhat speculative.  But it's also an intriguing one, and there are some analytical approaches that one can take to help remove guesswork and rather be informed speculation!  And that is the purpose of this post!

So, what effect did the wind have on Mutai, Mosop and co?

The mathematical approach - drag, wind resistance and improvement

I must confess this is not my first approach to the problem, but it is the best one.  My first approach is physiology and the physiological variance in performance, combined with historical context, as you'll see below.  But if you have the physics, then this approach brings some objectivity.

The two problems with this are that you need to make some assumptions about how to treat the runner - a cylinder with a given drag, and an assumed mass and height.  Also, you cannot always know that the wind is from behind, and nor do you know its speed the whole way, so there are estimates, but I still feel you still get valuable information given the length of the course, provided you make valid inputs.  It gets us into the ballpark.

So thanks to djconnel and Giovanni Ciriani for their inputs on this, which I'm pasting directly below:

Assume a human is 1.7 meters tall by 40 cm wide, with Cd close to 1 for a cylinder with normal wind incidence.  That's CdA = 1.5 meters squared.  Then assume the wind is blowing at around 2 m/sec (very fast for road-level given how fast these guys are running) with an air density near 1.2 kg/m-cubed.   That's 6.25 N = 6.25 kJ/km.   Minetti measured close to 3.4 kJ/km/km for running: http://jap.physiology.org/content/93/3/1039.full.  So if a runner weighs 60 kg, that's 204 J/m, of which the tailwind is saving 6.25 J/m, which if speed is proportional to power, is 3.8 minutes saved. (courtesy djconnel).   

 So that's 3 min and 48 seconds.


And then there is this, the wind resistance and relative velocity argument:

Aerodynamic drag for a runner is about 3% of forces acting against him/her. Today's wind in Boston (according to wunderground.com) was 14 mph W to E, which is just about the same speed the top runners were running at. Therefore the runners didn't experience aerodynamic drag. Since their power output remained the same, a 3% advantage translates directly into a 3% higher speed, and a 3% lower time = 3 min and 36 sec. (Courtesy G. Ciriani)

I'm going to work with an engineer to see if it's possible to refine the assumptions a little and work towards a clearer understanding of the physics.  However, we're in the ball park of 2 to 3%, 3 to 4 minutes.  Now, let's compare that to performance variations.

Historical approach.  Understanding the context of performance, Boston vs other marathons

I'm a big believer in history, as it applies to performance.  That's both "institutional history" and individual history.  Historical context is important, because it points to what should be expected in terms of improvements in performance.  Outliers happen, yes, like Bob Beamon almost jumping right over the pit in 1968, but when this happens, there is often an explanation, or at least part of one.  That's the value of context.

And so when you have an outlier, historical lessons become even more valuable.  2:03:02 is an outlier, because it's almost a full minute faster than the current record, and it was achieved on a course that is generally recognized to be slower than the other big city courses (with the exception of NY).

So the first way to examine the effect of the wind on Mutai's performance is to ask how large an outlier it is for the Boston course specifically?  The graph below shows the winning times in Boston since 1990.

The average winning time, excluding today, is 2:09:20, and interestingly, in the last TEN years since 2000, it has been 2:09:30.  Boston is one of the few major marathons where times have NOT plummeted in the last decade.  If you would rather compare Mutai to the best ever in Boston, then the previous record, only one year older, is that of Robert Cheruiyot, at 2:05:52.

So Mutai is 6:18 faster than the average and 2:50 faster than the next best time in Boston's history (with the exception of positions 2,3 and 4 in the same race, of course!).  It's important to start with Boston-comparisons only, because as we'll see shortly, Boston cannot be directly compared to London, Chicago or Berlin without some correction for Boston's hills and slower course.  What is more, the top four today all bettered the previous fastest Boston time by a considerable margin, since Hall finished in 2:04:58 to claim fourth.

Clearly, the wind had a significant effect on today's times, unless you believe that Mutai is genuinely a 2:03:02 guy in Boston, and by extension, that Mosop is at the same level, two minutes faster than the next best ever.  You also have to believe that Hall is a 2:05 or faster runner on a hilly course (which many feel doesn't suit him).

And remember, these are all Boston times, and the flaw in the argument becomes apparent when you consider how "slow" Boston is compared to other big city marathons, as shown below:

So Boston "expects" to be 3 minutes slower than the big European races (Rotterdam is as fast, incidentally - we just don't have the times going back 10 years), and 2 minutes slower than Chicago.  Recall that London has been won in 2:05:10, 2:05:19 and 2:04:40 in the last three years.  Berlin - 2:03:59, 2:06:08 and 2:05:08.  Boston?  2:07:46, 2:08:42 and 2:05:52.  Cheruiyot's sub-2:06 brought that down last year, the gap was 1 minute (I don't know the wind conditions then though), but generally, it's 3 minutes or more (Yes, there are years where Boston is super slow, and there are years when it is much faster, but last year, the 2:05:52 was the first time ever that Boston was within a minute of the other races.  So I don't think it's unreasonable to view Boston as slower)

Mutai vs Boston vs flat courses

This helps us understand where Mutai's performance ranks.   If you believe Mutai is a 2:03:02 man in Boston, then you're either saying that hills don't affect him, or that he could be a 2:01 performer or better in London and Berlin!  So we have something of a circular argument, it has to be said.  If you believe that Mutai is genuinely 2:03:02 material, then you can dismiss the impact of the wind.  But if you believe him to be a 2:05 runner, maybe 2:04:00 on the right day, then you have a wind impact of between 1 and 2 minutes COMPARED TO A FLAT COURSE.  Now add the Boston "disadvantage" due to hills and the wind is again coming out to 2 to 4 minutes, depending on how much Mutai may have been affected by the hills.

The point is, it's not valid, under any circumstances, to compare Boston times to those of London or Berlin.  Normally, it's for the opposite reason - Boston is slower.   Today, it is the other way around, and that is significant because it helps us understand just how big an effect that tailwind might have had.  In other words, the wind was at least sufficient to overcome a historical difference of 2 to 3 minutes on these other races. 

But Boston is now a minute faster - the wind was responsible for overturning a 3 minute deficit and turning it into a 1 minute advantage.  The wind is therefore estimated to be worth 4 minutes, based purely on historical averages (note that this approach assumes equality of strength of the races over the years, as well as the quality of the athletes at the top - I think this is a sound, valid assumption given the short three to five year period, others may disagree.  Certainly, there was a time when Boston attracted "lesser" runners, but the last five years have been comparable to London, Chicago, Berlin)

If one makes the admittedly tenuous leap that Boston is around 2 to 3 minutes slower, then this 2:03:02 in Boston is worth a...better than a 2:01 in London.  Only an extreme optimist would suggest this, and that's partly because we understand that such dramatic improvements don't happen, and because we know the characters.  So next, we need to look at Mutai, Mosop, Hall and co and ask if these individuals are running "out of character"?

Within runners - an error-prone comparison, but valuable with interpretation

Comparing the same runner in two different events can be fraught with danger, but if you are sensible, there's valuable information there too.  The reason for this is physiological variance - elite runners at this level can have bad days, where they are minutes off their best (Kebede in London may be an example of this.  Cheruiyot yesterday is another).  But when they have great days, they don't go minutes faster.  If you are an elite (and by this, we're talking top 20 ever), you don't leap forward by minutes in one race.  That happens to a Keitany, who has run a "slow" marathon in New York on debut, and then blasts 9 minutes faster in London.  That's not that unexpected, given the context.  But for the already established elite, there is such a thing as "acceptable physiological/performance variance".

So we accept the limitations, but use this to give more context to the physics and the history that we've already discussed.  

Let's take Mutai.  He has shown his marathon credentials on the fast, flat European races, first by running 2:04:55 in Rotterdam, and then 2:05:10 in Berlin.  To improve by 1:53, on the toughest of the three courses, that's a huge improvement.  And yes, runners have breakthrough days, but that margin is too large to simply be a "good day".  At this level, once you're in the top 10 in history (which Mutai was even before today) improvements of 20 seconds are remarkable.  Gebrselassie has set two world records, one by 29 seconds, the next by 26.  Those are breakthroughs for this caliber of athlete. 

1:53 is thus artificially high.  So assume that Mutai was in the same condition as Rotterdam and Berlin, when he ran very close to 2:05 both times.  Then, in Boston, he runs 2 minutes faster on a course that is normally about 2% slower than other courses.  If you assume that Mutai was in great shape, 30 seconds faster than Rotterdam (a huge leap forward in performance), then you still have the wind helping him to the tune of 1:30 compared to a flat course...

Knowing your history and where Boston lies, you know have the worst case where you have to also add time for the Boston profile.  2 minutes?  That's a conservative estimate based on history?  Then suddenly you have between a three and four minute difference made by the wind.  I suggested this in my first write-up after the race, and the physics calculations (assumptions and all) support the estimate - 2 to 3%, 3 to 4 minutes.

To return to the earlier example, if you believe the wind was worth only 1 minute today, then you're effectively saying that Mutai is a 2:04 guy in Boston, which means a 2:02 or better performer in London or Berlin (1 to 2% faster).  Either that, or that he is "immune to hills". 

The same is true for Ryan Hall.  A 2:06:17 runner, Hall has raced the marathon numerous times.  In his case, you have two Boston performances to compare to - a 2:09:40 and a 2:08:40.  Maybe Hall continued his improvement and was in 2:08 or even 2:07:40 shape this year.  He still ran a full 3 minutes faster than this. 

Of course there is variability in performance.  Athletes improve, they get worse.  But by seconds, not minutes in this population, and a three minute improvement, suggests to me close to a 3-minute impact by the wind, if not more. 

For an illustration from years gone by, the last time we had such strong tailwinds in Boston was 1994.  That year, Cosmos Ndeti won the race in a course record that was bettered by only two men until this year (both Cheruiyots, one in 2006, and last year).  Now there are four men going under 2:05 in one race.

But back in 1994, America's Bob Kempainen produced a "Beamonesque" performance by running 2:08:47, which was an American record at the time, and would remain so until Ryan Hall broke it.  Kempainen was a good, but not great runner, and his next best time was 2:12:45.  That's a 3:58 improvement, on the tougher Boston course, thanks to a windy day like we had today.

Yes, there are factors that influence this, which is why his numbers alone don't make this case. But when you have Boston's history, plus the comparison between Boston and other races, plus Mutai and Hall's recent racing credentials over Boston AND other courses, then a picture starts to come into focus.

The pacing and 2:03:02 performance in context

So how big an effect did the wind have?  Impossible to say.  Can we conclude that the wind was worth about 3 to 4 minutes? 2 to 3%  I suspect so.

And so while Mutai's time is exceptional, I would interpret it differently.  2:03:02 is superb running - on the hills of Boston, wind or not, it defies belief.  A second half of 61:05 is eye-popping.  But if that wind is genuinely worth 2 to 3%, as I suspect, then the first half of 61:57 is actually worth about a mid-63 minute first half.  In other words, conservative.  That suddenly explains the searing pace in the second half, and it also helps us understand those final 10km.

The final 10km are also mostly downhill and so a 28:25 is extra-ordinary, but with a wind of even 2% (conservative), plus a relatively physiological "conservative" start, and the ingredients were there for a super fast finish, and an amazing overall time!

I guess we'll never know, but we have a great fall marathon season to look forward to!

The fall marathons and the impact of Boston

What will be fascinating is to see how this impacts the Fall marathons, particularly Berlin.  It's like that Geoffrey Mutai will race there.  Maybe even against Emmanuel Mutai.  And Wanjiru.  Will the elite men, having now touched the 2:03 barrier try to go out in 61:30 for the first half?  That would be faster than Boston's first half, without the downhill start and the following wind, so it's adventurous, but does Boston 2011 change the mindset of the elite?

And if the top men, in a race, do go out in 61:30, or even 61:15, will that pace be sustainable?  That's a fascinating question, and it sets the fall marathons up in a big way.  Remember that until yesterday, only Haile Gebrselassie and Emmanuel Mutai had broken 62 for the second half of a major marathon.  Now we have Geoffrey Mutai and Moses Mosop.  Is that possible with a 61:30 first half?  My initial thought is that a first half of 61:15 to 61:30 is just too quick, for now.  61:45, followed by a 62 min is doable, if the weather conditions are perfect in Berlin, perhaps.

But that's all conjecture - let's wait for October to see!  Marathon running has never been healthier!

Ross

P.S.  A late addition to the post. In the discussion to the previous thread, we received a comment from Mike with this link to a running calculator based on Jack Daniels' formulas for pace.  In this calculator, if you assume that the wind was 14 mph tailwind, then the predicted time with zero wind is about 2:10.


There are clearly differences in how the wind is assumed to impact performance!  And our 2 to 3% conclusion in the post above, aided by the physics of some readers, seems to be on the conservative side!  I suspect that this calculation is "idealized" and what you'll probably find is that the variable wind speed and direction in "real-world" Boston conditions, combined with shelter, combined with the different physical stature of runners, accounts for differences.  But overall, I'm pretty confident (but never certain) in the estimation of 2 to 3%, or 3 to 4 minutes thanks to yesterday's wind in Boston.

Boston Marathon preview

Boston on the horizon: Wind at the backs, another Mutai win?

After yesterday's spectacularly fast London Marathon, there is more in store today as the rest of the world's elite hit Boston in the 115th running of the world's oldest annual marathon.

The weather forecasts for Boston give reason for optimism for fast times.  Below is an image taken from this Letsrun article, and it shows that the forecast for Boston is about as good as one can possibly expect - cool, with a following wind that, because of Boston's point to point orientation, is basically from behind the whole way (click to enlarge)

That has led to speculation about what the elite field might be able to achieve, some even predicting a time faster than 2:03:59.  It must be pointed out that this would not be recognized as a new world record, because of Boston's point to point course, but it may make for some spectacularly quick times, or splits at the very worst.

Last year in Boston, Robert Cheruiyot achieved what no one thought possible - a sub 2:06 clocking when he scorched the relatively tough course on route to a 2:05:52.  It included an exceptional second half of 62:25 that includes the Newton Hills, and it was a performance that many suggested was worth something in the 2:03-range on one of the faster marathons around the world.  You can read our recap of that race here, just to get in the mood for later.

I can't quite see a sub 2:04, regardless of wind, but if that tailwind does deliver, then we may well see a new course record, particularly given the strength of the field - in addition to Cheruiyot, there is Geoffrey Mutai and Gebre Gebremariam, two exceptionally strong runners, who I'd make favourites ahead of Cheruiyot.  My picks would be Gebremariam to win, Mutai in second, with either Cheruiyot or debutant Moses Mosop in third.

The women's race was also exceptional last year, a real race to the line between Erkesso and Pushkareva.  Last year Erkesso did a "Keitany", in that she went hard very early and built up a big lead.  What she didn't do is hold it all the way, and Pushkareva almost caught her before losing out by 3 seconds in the final straight!  Boston has in fact produced incredible races in the last few women's events, and this year should be no different.

For race previews and to learn who the main protagonists are, check out the Men's Preview and the Women's Preview, courtesy Letsrun.com

As is now "tradition", we'll do a live post throughout the race, updating a table with splits and projected times, as well as 'play-by-play' commentary and thoughts from the race.  So if for any reason you can't get to a TV, do join us later for coverage!  (Assuming Universal Sports' feed works - it wouldn't be the first time I fail to see a marathon as a result of problem...but will do my best!)

Ross

The Sub 2 Hour marathon debate

The sub 2-hour marathon:  Science fact and projecting performance

I hate repeats.  Well, that is, I usually hate repeats, unless there's a very specific reason to watch the same thing twice.  And I figured that with the London and Boston Marathons only a few days away, there is no better time for a repeat than today.

The BBC yesterday did a radio show and carried this article on the possibilities of a sub-2 hour marathon.  The article is interesting and it touches on most of the points that we have looked at in the last few years, because this is by no means a new debate.  In fact, it seems to cycle around once every six months on the marathon-carousel.  Every time we have a big marathon on the horizon, people ask this question.

Personally, it seems a bit premature to me to be talking about a sub-2 hour marathon now, when the first human performance under 2:04 was as recent as 2008.  And then, by only 1 second!  To knock off another 240 seconds and break that barrier is getting a little carried away.  Let's get under 2:03 first, and then see how the future looks! That could easily take two generations of runner, another 10 years.  The big names are weighing in though - Gebrselassie and Radcliffe (who know a thing or two about marathon records) both suggest it will happen within 20 years.  A scientist predicts 28 years.  I suspect they're all a little optimistic...

The scientific merit - digging deeper

However, it is a question that has a great deal of scientific merit.  Both the mathematical modeling of performance evolution and the physiology of breaking 2 hours in the marathon are extremely interesting, and that's where the BBC article doesn't quite do justice to this question.

That is, the BBC touch on all the aspects - they mention the history, the evolution, the physiology that may be required, and the conditions that have to come together, but they varnish the surface rather than really getting stuck into it.  And so with that, I thought I'd take the opportunity to re-post an article I wrote about 7 months ago.  It asks "What is the physiology required for the 2 hour marathon?"  That article is below.

That article is below.  Also, the question is discussed from a historical point of view and using a slightly different approach to what you'll normally read in the media, in the following posts:

• Who will break 2 hours for the marathon?  And when?  Lessons from the shorter distances
• Why the marathon record was destined to drop, and why it may be about to level off again

Hopefully those three can keep you intrigued while I get my head around 10,000 hours and the next in the series on training and talent development!

Ross
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The sub-2 hour marathon: What physiology will it take? (originally published September 4, 2010)

The other day, I did a post looking at the likelihood of a sub-2 hour marathon, inspired by an interesting article published in the Journal of Applied Physiology.  That was part 1, focusing on the historical evolution of world records, not only in the marathon, but over shorter 10km and 21km distances, because I'm of the opinion that a 2-hour marathon will only be possible when the 10,000m times and half-marathon times improve by at least 30 seconds and 90 seconds respectively.  So, contrary to the JAP paper, which suggested that the barrier would be broken in between 15 and 25 years, I think it will take many, many more years.

Today sees the promised Part 2, looking more at the physiology, and specifically the running economy that will be required in order to reel off 42,195 m at an average pace of 2:50/km.  It's a conceptual post, so bear with the length and the "unanswerable" questions.

And I must emphasize the point, picked up by some of you, that physiologically, our ability to separate a 2:03:59 from a 1:59:59 is limited.  Both performances are close to the "limit", and given that elite athletes are rarely tested and measured in the laboratory, and that the physiological variability is larger than the difference in performance we're looking for, you won't reach the end of this kind of discussion with a concrete answer.  However, it's an interesting process, nonetheless.

Running economy re-introduced

Way back in 2007, we did a short series on Running Economy, the first post of which can be read here.  Running economy is a measure of how much oxygen you use when running at a given (sub-maximal) speed.  The more economical the runner, the less oxygen is used, and this is crucial, because it is a characteristic of great runners that they are much more economical.

The graph below, which is redrawn from a paper by Foster and Lucia (2006), shows the running economy of a few different groups of runners.

Here, running economy has been measured as the volume of oxygen used per kilogram to run one kilometer (think of fuel economy in a car - one gallon takes you x-kilometers).  So, the Europeans shown by the pink line in the above graph are using approximately 210 ml/kg to run 1 kilometer.  You can convert this to the actual VO2 quite easily, if you know the running speed.  For example, at 20km/hour, 1 kilometer takes 3 minutes, and so these European athletes are using 70ml/kg/min at that pace.

The Africans, shown in red, are considerably more economical (this is one of the more interesting debates in physiology - there are obviously overlaps, but generally, African runners appear more economical than Europeans).  The VO2 of the Africans at 20km/hour is equal to 190 ml/kg/km, or around 63 ml/kg/min, about 10% lower than the Europeans.

Can economy and capacity predict performance?

So, knowing this, we can begin to project what kind of physiology is required in order to run a sub-2 hour marathon.  The method used is very similar to that used for cycling, when we looked at the power outputs achievable during the Tour de France in our recent Tour coverage.

There are of course assumptions that must be made, but as I tried to explain for cycling, if you make the "conservative" assumptions, you still produce an interesting picture of what is physiologically plausible.  This is an exercise in theory, not proof.  It is the first word in a debate, not the last, so bear with some assumptions and let's see what the picture reveals.

The assumptions

The first assumption that you have to make is what relative intensity an athlete can sustain for a given period, two hours in this case.

This is not too much of a guess for elite athletes, but it does vary considerably with training - an elite athlete is usually able to sustain running speeds that require about 85% - 90% of VO2max for about one hour.  Marathons are usually run at an intensity corresponding to approximately 80% of VO2max, while 10,000m is run at around 95% of VO2max.

So for a two-hour marathon, we can make the assumption that the intensity will be equal to between 80% and 85% of maximum.

Next one has to assume VO2max, the "capacity".  This is more of a lottery, because the range, even in elite athletes, can be quite wide.  Zersenay Tadese of Eritrea was measured at 83 ml/kg/min, but some elite runners have been measured as low as 70 ml/kg/min (the reason they are still competitive, incidentally, is likely due to exceptionally good running economy). 

And then finally, you must assume running economy.  This is the key assumption, because as the graph above shows, it varies quite considerably.  The east Africans have been measured as having running economies in the range of 180 to 190 ml/kg/km.  Zersenay Tadese was reported to be the most economical runner in history, using only 150 ml/kg/km.  This is so low that I'm actually skeptical about the value.  (For more on this, check out this post from 2007, and see later in this post)

Nevertheless, using three assumptions, we can create quite an interesting picture of what the sub-2 hour marathon runner will look like, at least in terms of his 'engine'.

The graph below is the first step towards bringing all three assumptions together.  It converts running economy into a VO2 (in ml/kg/min) at 2-hour marathon pace (± 2:50/km).

Obviously, this picture is only partly complete.  The next question to ask is whether an average VO2 of say 67 ml/kg/min for a marathon (at the running economy of 190 ml/kg/min on the graph) is reasonable or not?  Can an athlete sustain that intensity for the required 2 hours?  Obviously, this question is not answerable in theory, only through measurement, but we can get an idea of whether it is reasonable by asking what kind of maximal capacity is required for each of the above VO2 values to be reasonable.

The graph below attempts to establish this.  It estimates the VO2max of the runner for two conditions:  One is that the athlete is running at 80% of maximum intensity (shown in red) or 85% of maximum intensity (shown in green).

So, for a given running economy, you can now see what maximal capacity might be required, or vice-versa, given a VO2max, you can estimate the running economy required for two different conditions.

Two examples:  High economy vs lower economy

The white lines show 2 examples.  Example A is based on the measured economy of African athletes (including some Olympic medalists) who have a measured economy of around 190 ml/kg/min.  At 2-hour marathon pace, they use 67 ml/kg/min.  That athlete, running at 80% of maximum, must have a VO2 max of 84 ml/kg/min.  If they were able to sustain 85% (which I don't think is possible), they would have an estimated VO2max of 79 ml/kg/min.

Example B shows the European athletes plotted in the very first graph of this post.  Here, a running economy of 210 ml/kg/km requires a much higher maximal capacity; in this case, either 92 ml/kg/min (at 80%) or 87 ml/kg/min (at 85%).  The point is clearly that in order to run a sub-2 hour marathon, the athlete requires BOTH an exceptionally good economy, and a high maximal capacity.  I guess the third option is that they could get away with worse economy if they were able to sustain 90% of maximum for that length of time, but I don't see this as very likely (but not impossible).

The Zersenay Tadese example:  Something missing in the picture

So where does this leave us on the question of the sub-2 hour marathon?  On paper, or in theory, a two-hour marathon is possible because we have seen running economies of 180 to 190ml/kg/km, and we also see runners with VO2max values of 80 ml/kg/min.  According to the graph, a runner with these "characteristics" can run the 2-hour marathon.  However, I've yet to see the two together, with the exception of  Zersenay Tadese, with his measured economy of 150 ml/kg/min and VO2max of 83 ml/kg/min.  However, as I said earlier, there's something not quite right there...

Here's the problem:  With that kind of economy, Tadese would be able to run at a speed of 2:50/km while using only 53 ml/kg/min.  Think about that for a moment:  he is running at only 64% of his maximal capacity, at 2-hour marathon pace.  He would be jogging to the world record if that was true.

Even his 10km pace of ± 2:40/km represents an underperformance, because at that pace, he would only be using 56 ml/kg/min, or 68% of his maximum.  We know that elite athletes run at at least 90% of maximum for 10km, which means Tadese should be sustaining a VO2 of 75 ml/kg/min, which, given his economy, predicts a 10 km time of just outside 20 minutes!

Clearly, something is wrong with that picture.  I actually emailed Carl Foster about this a while back, to ask about it, and he graciously replied, but then my computer got stolen, along with that email.  So Carl, if you are reading this, feel free to chime in!  I seem to recall that it had something to do with the timing of measurements - Tadese's VO2max and running economy were not measured at the same time, and therefore using them together created a problem.  And this is crucial - when we make this kind of estimation, we're assuming that VO2max and economy are measured together.  And if they are, then the more economical a runner, the lower their VO2max is likely to be.

The VO2max-economy relationship

For this reason, the combination of high VO2max and exceptional running economy is likely to be very rare.  So, let's get back to that graph above - does the athlete shown by "Example A" exist?  Is there an athlete with such exception economy AND such a high VO2max?  Or is the athlete with that economy likely to have a VO2 max closer to 70 ml/kg/min?

That is a question I don't have the answer to.  What is clear though is that even now, the current world record represents physiology that is close to this theoretical picture presented above.  That is, the current record equates to a runner with an economy between 180 and 200 ml/kg/km and a VO2max between 75 and 85 ml/kg/min.  Both of these are reasonable assumptions, which would lead one to conclude that a sub-2 hour marathon is physiologically plausible.

However, as I emphasized in my previous post, it's not as simple as this.  First, there are other "limiting" factors - thermoregulation is one that has not been mentioned yet.  To run a sub-2 hour marathon requires significant heat loss to offset the heat production, and so the limit may well have little to do with oxygen use, and everything to do with the avoidance of hyperthermia.  This factor certainly narrows down the opportunities to break the world record, because only a cool day will suffice - Dubai, Berlin and Chicago have all produced days that are too warm in recent years.  As the 2-hour mark is neared, that becomes even more crucial, and that's a big reason why I don't think we'll see more than one, small incremental improvement every five or so years.

And then finally, I must stress that this 'pre-occupation' with VO2max and oxygen as the determinants of performance is only part of the picture.  Performance is the sum of far more physiology than just VO2max and economy, and that's why the best indication of whether that sub-2 hour performance will be possible is, in my opinion, to ask what the implications are for performance over other distances.  If the shorter distances don't improve, then the longer one is unlikely to, and you can go through this same exercise for 10km and 21km events and you realise that we're right on the limit of physiological performance.  Doping would shift that limit, yes, and perhaps training.  But I still don't see it happening within the next 20 years.

Perhaps I will be wrong...as always, your thoughts are welcome!

Ross

The sub-27 10km limit: An exclusive club

An exclusive club of sub-27 minute 10km runners

So it turns out that over 3,000 people have summitted Mount Everest.  Only 31 have broken 27 minutes for 10,000m.

Admittedly, no-one has died ever trying to break the 27-minute barrier (at least, not directly during the attempt), whereas more than 100 people have died trying to reach the earth's highest point.  But it's amazing to think that this exclusive club, consisting of only 31 men, had never had a non-African in it, until last weekend.

Now, Chris Solinsky is a member, the first man from outside of African to break the barrier.  The other day, we also reported on LetsRun.com's analysis that Solinsky is the heaviest athlete ever to break the barrier, and by some margin.  Just to repeat, below is a very basic graph of the sub-27 club members, showing the mass of the runners by rank, and you'll see the obvious outlier that is Solinsky in red.

It turns out that the average mass of the men in this list, without Solinsky, is only 55.6kg.  The heaviest, as mentioned the other day, were 64kg.  In other words, only small men need apply!

There was some quite good discussion in response to that post.  Size in distance runners has received quite a lot of attention in the literature - about 10 years ago, Frank Marino did research showing that smaller men had a performance advantage over larger men during 8km time-trials in hot, but not cold environments (Marino et al. Pflugers Arch, 2000).  That is, they performed similarly in cool conditions, but as soon as it got a little warmer, the smaller men outperformed the bigger men.

What was most interesting is that the bigger athletes started the trial at a slower pace, probably an anticipatory reduction in speed so that they wouldn't overheat.  Why?  Because the bigger you are, the more heat you produce during exercise, and even though it is possible to lose more heat, it doesn't quite make up for the extra heat gain.  As a result, the larger athlete stores more heat, sees a more rapid rise in body temperature, and thus selects a lower speed in anticipation of this "thermoregulatory failure", and is thus outperformed by the smaller athlete.

This is not the sole reason why smaller men have the advantage - there is the obvious advantage of carrying additional weight, a power-to-weight ratio, that gives the smaller men at advantage.  Particularly in cooler environments, where heat storage and the attainment of a critically high core temperature are unlikely, thermoregulation is much less of a factor (hence the reason that the two groups in Marino's study performed similarly in the cool condition).

A first-of-his-kind member - a non-African joins the club

But in terms of size, the other thing that jumps out from Frank Marino's study on size, is that he could just as easily have analyzed his results by ethnicity.  It turns out that the smaller men in his study were African, whereas the larger men were European/white. And so, he duly did this - produced a second paper showing what he called "Superior performance of African runners in warm humid but not in cool environmental conditions" (Marino et al., J Appl Physiol, 2004).

So the African runners tended to be smaller, and this was postulated to be part of the reason for their advantage.  Note that I'm saying "part of", because of course there are many, many factors that contribute to their advantage - training, culture, diet, altitude, lifestyle, genetics, biomechanics, metabolism, and then thermoregulation.

But it is striking, and the other notable observation of Solinsky's performance is that not only is he the largest runner every to make it into the sub-27 club, he's also the first man from outside Africa to do.  Of the 31 members, 20 are Kenyan (including a few who happened to be running in Qatar vests), 6 are Ethiopian, 2 are Moroccan (one of whom ran for Belgium and then got caught doping), and one each for Uganda and Eritrea, and now America.

I could go on for hours and hours about why this might be, but I haven't the time right now, unfortunately.  The African dominance in running is well-known by anyone who follows the sport - I dare say that in some respects, it's a problem for the sport because the sheer depth and quality of the Kenyan and Ethiopian athletes makes in much more difficult to follow the sport with a passing interest - you're either a full fan and know the characters, or it is almost overwhelming how much talent comes through year after year if you don't follow it closely enough.  I think it's fantastic to watch the races which are less predictable, and I find this a source of strength, but to the "marginals" with only a passing interest, the continued dominance does present a challenge to marketing the sport.

There is a lot to be said for the value of "stability" of athletes in sport - in tennis, you know that Federer, Nadal and Djokovic will build a great rivalry over many years.  In distance running, it's much more transient, partly because of the depth.

I am reliably informed by colleagues in sports science in Nairobi, that many Kenyan athletics meetings feature no hurdles events, no field events, and few sprint events, but they do have ten 10,000m races, each with 30 runners, and every single one breaks 30 minutes!  At altitude.  There are a lot of "myths" about the sport in Kenya - this may be another where the truth expands every time it's told!  But one thing that is without question is that for sheer depth of talent, they are unmatched, and hence for quality, with the right management and coaching support, they produce two-thirds of the world's great runners.  They may have relatively short-spans at the top (this would make for a fascinating analysis), but they certainly dominate.

So it's a breakthrough, and again, that sub-27 minute club is unbelievably exclusive.  By way of comparison, there are 72 men who have broken 13-minutes for 5km, which is the other barrier often spoken of for track distance runners.  Admittedly, 10,000m is raced much less frequently than 10,000m, but it highlights how special a sub-27 minute time is.

Coming soon - more on hGH

We haven't forgotten about the Growth Hormone paper, which has now been published.  We have it (thanks, Andrew) and we'll have a look at it.  Both been incredibly busy though, so that in-depth reading will have to wait, hence these shorter, "filler" posts.

But watch this space!

Also, the FIFA 2010 World Cup is now just over a month away.  Being in South Africa, it would seem wasteful to not use the opportunity to do some posts on the science of soccer.  I'm actually about to give a talk on this within the department, so I'll be offloading some of that here in the coming weeks!  Much to look forward to!

Ross

London 2010 Live post

London 2010 - splits and comments

Kebede and Shobukhova win as other favourites struggle

Tsegay Kebede of Ethiopia has gone one better than in 2009, and has won the 2010 London Marathon in 2:05:19.  The race was unlike London Marathons in recent memories, because it didn't come down to a big group of men with 5km to go.  Instead, the damage was done soon after halfway, when a 5km split of 14:26 split the elite group wide open.

This surge accounted for Sammy Wanjiru, Duncan Kibet and Zersenay Tadese, three of the big, big favourites in the race.  They were blown right out of the group.  Instead, it was Emmanuel Mutai, Abel Kirui, Jaouad Gharib and Tsegay Kebede who emerged at the front.  The next 5km, from 25km to 30km, was covered in 14:27, giving the elite men a split of 28:53 between 20km and 30km.

That is of course a fierce pace, but it was surprising that the elite field was so fragmented by this pace.  Certainly, Tadese, Wanjiru and Kibet have the capacity to run the pace, but today were simply outclassed.  It's not even as though they hung onto it for a short time, they were completely shot out the back of the group.

Kebede, on the other hand, thrived, and he covered the 21st mile in 4:33, which accounted for the brave efforts of Abel Kirui.  From that point on, Kebede was unchallenged, and his lead grew progressively.  The eventual margin of victory was 1:04, over Emmanuel Mutai, who caught a dying Kirui for his best London finish.  Gharib of Morocco finished strongly for third.  Kirui, meanwhile, paid for his efforts, finishing fifth.

As for those other favourites, at the time of writing, only Tadese finished, well down and looking well beaten.  Wanjiru and Kibet presumably stepped off the road somewhere between halfway and 30km, to fight another day.  For Wanjiru, it's a first disappointing performance in a major marathon.  For Kibet and Tadese, it's two-in-a-row, following last year's failures in Berlin and London, respectively.

I'm sure there will be much discussion of what happened in the aftermath - perhaps back troubles for Wanjiru, plus the travel difficulties, will come up.  For Tadese, I just wonder if he's got the training figured out.  How someone with a 58:23 half-marathon is be dropped just after halfway when the time is 63:10 is beyond me.

Women's race

On the women's side, it went more according to script, both in terms of the pace and the way it unfolded.  Early on, the pace was solid - on course for a low 2:22.  The pace started faster than this, and then dropped progressively up to the halfway point, where the pacemaker stepped aside.

Then it was Liliya Shobukova of Russia who took the lead, and continued to reel off 3:20s per kilometer, keeping the 2:22 within sight.  That was enough to progressively thin the field, with the resistance provided by Bekele and Mergia of Ethiopia, and Abitova of Russia.

Mergia threw in a big surge of her own at about 36km, and this accounted for Bekele and, for a short time, Abitova.  Shobukhova, however, looked untroubled and stayed with Mergia until the intensity dropped off. Then Abitova began to close the gap, and Shobukhova made the final, decisive move.  She moved away at 40km and went unchallenged to the line, finishing in 2:22:00.

It was actually a much closer race than the men's side, and Shobukhova gets my nod for the best performance of the day.  She was composed and in control the whole way.  After her searing finish in Chicago last year, you'd have forgiven her for following moves all day and waiting to the final 5km, but she didn't - she controlled the pace, did much of the work and in the end, was simply too good for the competition.

Overall perspectives

We'll give it much more thought and do our usual "race insights" post tomorrow, where we'll look more closely at the pacing and performances of the main runners.  For now, though, my impression is that the men's race didn't live up to the hype.  Yes, it was brutally fast between 20 km and 30km, but I really did expect it to be closer.

Kebede was a deserved victor, but when you look at the times, and the fact that for example, 10th place was 2:16:38, then you would be surprised to learn that this was the strongest field ever assembled.  Perhaps too much was expected, but I certainly thought it would be the deepest race ever, and if you'd said that fifth would be outside 2:08, I'd have dismissed that without a thought.

On the women's side, it was a better race, with more depth.  Most of the top women ran quite big PBs, and Shobukhova confirmed her status as the premier marathon runner at the moment.  Yes, the time was not spectacular at 2:22:04, but for competitive depth and quality, it lived up to the hype.

More to come - we'll have a closer look at the pacing and see how it unfolded, and add some insights on who thrived, who failed, and why.  So join us for that tomorrow!

Ross

Live coverage and splits below

For those who missed it, and want to follow it as it unfolded, below you can read the comments during the race, and also see the race splits.

Splits

Distance	Time	Interval time	Pace for interval	Projected time
5	14:39	14:39	2:55.8	2:03:38
10	?
15	44:51	30:12	3:01.2	2:06:10
20	59:53	15:02	3:00.4	2:06:20
Halfway	1:03:10			2:06:20
25	1:14:19	14:26	2:53.2	2:05:26
30	1:28:56	14:27	2:53.4	2:04:51
35	?
40	1:58:41	29:55	2:59.5	2:05:12
Finish	2:05:19	Kebede
Distance	Time	Interval time	Pace for interval	Projected time
5	16:33	16:33	3:18.6	2:19:40
10	33:17	16:44	3:20.8	2:20:26
15	50:11	16:54	3:22.8	2:21:10
20	1:07:18	17:07	3:25.4	2:21:59
Halfway	1:10:56			2:21:52
25	1:24:04	16:46	3:21.2	2:21:53
30	1:41:08	17:04	3:24.8	2:22:15
35	1:58:25	17:17	3:27.4	2:22:46
40
Finish	2:22:00	Shobukhova

 


Race Comments

Women's start 

Seems I spoke to soon.  The commentators include Eammon Sullivan, who last year couldn't pronounce any elite names.  20 seconds in, and he's butchered Mikitenko's name.  Pity Martin Lel is not running, he may actually get that one right.

The early pace is steady, as the pacemaker has gone well clear of the field, who only now, just over 2 miles in are catching her.  They're on 2:22 pace, which is pretty much as expected.  About 14 women in the main bunch, but by halfway, expect that to be much thinner. 

Women 5km 
16:33 to 5km, so that's 2:19:40 pace, but aided by a fairly steep downhill section.  The roads are very wet, so while the sun is not out, the roads will likely factor at the end of this one.  Still a big group together.

Women 7km 
The group is now a little thinner, but only one pacemaker present, which is unusual.  It seems the commentators don't know that Shobukhova won Chicago last year - they've just referred to her as an unknown quantity, who is new to the marathon.  

Women 9km 
Plenty of footage of Mara Yamauchi so far, not surprisingly.  She, like many of the athletes, endured a length trip to get to the start line, thanks to the travel chaos last week.  It will be interesting to see how that affects performances.  Still 14 women in the lead group, one pacemaker in front.

Women 10km 
They've hit 10km in 33:17, so the pace has dropped only very slightly over the last 5km.  The group is pretty stretched out, so it should start thinning out soon.  

Women 13km

The pacemaker seems to be struggling, rolling side to side, the occasional grimace.  She doesn't strike me as capable of going much beyond halfway.  Shobukhova is looking very solid just off the lead, as are the Ethiopians.  

Speaking of struggling, Mikitenko is gone off the back of the lead group, that's her race pretty much over!  Big surprise - she probably wasn't fancied for the win, but few would have picked her to drop off a 13-women lead group inside the first hour!

Meanwhile, they're introducing the men.  Here comes the action!

Men's start

There are five pacemakers for the men, compared to only one for the women - this is as much a reflection of the quality of the fields and standards as anything else.  Last year, the men tore through 5km in 14:08 (and 10km in 28:30), so let's see if the same aggressive start happens here!

Women 15km

The women's pace has continued to drop off slightly - they're still on course for a 2:21:10, which is more or less what everyone had expected. The commentators are continuing to talk about Shobukhova as "inexperienced" and new to the event, even though she was third last year and won in Chicago.  They will certainly be surprised a little later, if she produces the win I certainly expect.

Men 4km

The pace is solid - about 4:48 for the first two miles, and the third one is fast downhill, so they're on course for a quick opening.  Not as fast as last year, though that's probably a good thing.

Men 5km

The split is in - 14:39, which is much slower than last year, and given the steep downhill 3rd mile, not that surprising.  The projected time is 2:03:38, but don't read too much into that.


The commentators can't pronounce Wanjiru.  Every time they say it, it comes out differently.  I can't understand how - he is only the favourite, and the defending champ, and the Olympic champion.  If there was only one name they should make sure of, it would be his.  Very poor.

Women 19km

The pacemaker has gone clear again, perhaps her last push before she drops out.  Or, maybe the elite field has lost momentum.

Women at halfway

The lead women are about to hit the halfway mark.  The time is about 1:11 (I didn't see it, because they cut away to the men).


Meanwhile, Mara Yamauchi has dropped off the lead group, which is a surprise. She was prominent at the front for the first 20km, and so her sudden "retreat" to the back is not a good sign for her.  I fully expect that later on, we'll spend time waiting for her finish in 2:26 while the men are at the 38 km mark.  Shobukhova is now at the front of the elite field.

Men 10km

The men's pace is quick, but not spectacular, which is a good thing. Last year was far too fast, and many marathons have been hindered by fast starts.  The group is spread out over the road, which is a good sign, because it means most of the men are holding back, not really being pulled along in a line.  The pace certainly won't drop off between now and halfway.  Struggling to get splits though.

Men 12km

All the big names are in the group - Wanjiru, Tadese, Kebede, Kibet, Mutai, Kirui, Gharib.   There are 12 in the group, but 4 are pacemakers, and all the main attractions are still present.

Women 25km

Not surprisingly, the pacemaker is gone, and Shobukhova is in the lead.  The pace actually picked up from 20km to 25km - the last 5km covered in 16:46.  The projected is now 2:21:53, and the group is now much smaller.  We haven't seen too much of the race in the last ten minutes, but there has to have been a small surge around halfway - it accounted for Mara Yamauchi and a few others.  There are now about 9 in the lead group, which is larger than I expected, I have to say.

Men 15km

I apologize for not having splits more often - the TV coverage is predictably uninformative.  If you know of live athlete tracking let me know.

Meanwhile, the men are through 15km.  It's anyone's guess what the time is.  It seems to be about 45 minutes, which is a little slower than I expected.  It's outside 2:06 pace, and as a result, the elite field is still bunched.

So the 15km split, unofficially, is 44:51.  That means the last 10km have been run outside 30 minutes, which is why the projected pace is now outside 2:06.  The pace has definitely picked up though, because the group is suddenly longer and sleeker, no longer spread out across the road.  The next split will be interesting - will be a little quicker, I suspect.

Women 29km

Shobukhova is still in the lead, setting a firm, but unspectacular pace.  There are eight other women in the group, including Bai Xue of China, and the Ethiopians.  Interesting that Shobukhova is doing as much work as she is - her finishing 10km in Chicago, and particularly the final 5km, was spectacular, and I'd have thought she might rely on that.  But perhaps she's looking for that 2:21 time as well as the win today.

Women 30km

The pace is solid - 17:04 for the last 5km, has them through 30km in 1:41:08.  The projected pace is now 2:22:15.  Solid, but unspectacular.  There are definitely signs that the pace will ramp up though, as the group has spread out and other athletes are pushing to the front for the first time since the pacemaker stepped off.

Men 20km

The men have run 4:50 miles for the last 20 minutes.  They've hit 20km in 59:53, which is still pretty sedate, I have to say.  The final 10km are going to have to be spectacular at this relatively slow pace.  There are 15 men in the lead bunch, none of the big favourites are absent.


The projected time is now mid-2:06 - 2:06:20.

Men halfway

The halfway point in 63:10.  Going through the water table, it did pick up a little.  I think the water-tables can be quite deceptive that way.  The size of the group is probably the best indication that the pace is not that quick - sure, London has a great field, but to have 12 men together at this point tells you that the pace has been steady and relatively unspectacular.

Women 32km

The lead group has thinned out steadily.  It's down to four now, and Bai Xue is not one of them, which is also a surprise.  Currently, Shobukhova leads, with Bekele and Mergia following most closely.  Ethiopia have had a brilliant marathon season, with wins in Paris and Boston, and vying for London today.  Also in the group are Abitova of Russia.  

Men 23km

The pace is still in the 4:50 per mile range - that's about 3:00/km exactly.  At this rate, they're looking at hitting 30km in 1:30:00, and then the race will really be on over the final 12km.  It should make for a spectacular race.

Men 25km

Huge explosion in pace - 4:33 for the 15th mile, and Wanjiru has NOT responded to that.  It was Mutai who threw in that move, and Kirui and Kebede were first to respond, and the defending champ was put into difficulty!  Wanjiru is gone!  Tadese is gone!  Kibet is gone!


The group has been blown apart by that move.  Tadese is hanging on, though more in touch that Wanjiru.  Kibet is off the pace too, he and Wanjiru are running together about 10 seconds back of the leader.  Gharib is there, but right now, it's Mutai, Kebede and Kirui, and one remaining pacemaker.


The last 5km were covered in 14:26, which explain what has happened to this group.

Men 26km

The pace is still high.  Dos Santos of Brazil is right at the back of the top group, and almost in touch.

Women 36km

The women are still in a group of four.  The pace has slowed - the last 5km were run in 17:17, the slowest interval of the race.  The commentator says they're "motoring" - they aren't.  But it is a tough race now, attritional.  Two Russians and two Ethiopians.  Shobukhova remains the favourite, but two Ethiopians in Bekele and Mergia Aselefech are perhaps the big dangers.

As I type that, Mergia Aselefech goes into the lead, and that seems to have Bekele in difficulty at the back of the group.  Shobukhova looks really comfortable to me, Abitova is still there.  Bekele is gapped, five meters back.  Now ten meters.  We're down to three.

Women 37km
Mergia Aselefech has continued to drive the pace, and now it's two!  Shobukova has hung on, as they've gone through the last mile in 5:18.  The fastest of the race.  Abitova is off the group, and now it's one Ethiopian vs one Russian.

Men 28km

The pacemaker is gone, and it's down to four.  It's Kirui, Kebede, Mutai and Bouramdane of Morocco the surprise package. The last mile was 4:38, and so the pace is still very fast.  The 5km from 25km to 30km is going to be spectacular.

Women 38km

The pace at the front of the women's race has slowed - Mergia threw in a surge but Shobukova was able to respond, and looked very comfortable doing so, I have to say.  Abitova has also held the gap steady, which will provide a good barometer of what is going on out in front.

Men 29km

Kirui and Kebede are out in front.  Wanjiru and Tadese are both well down, and neither is going to come back.  Mutai has seen a gap open in front of him in third, and so it seems down to Kebede and Kirui with fully 12 km to go.

Men 30km

Kirui vs Kebede.  My money would have to be on Kebede, but Kirui is running a brilliant race.  The pace has picked up incredibly - the last five miles were run in 4:36, 4:33 (the one that did all the damage), 4:51, 4:33 and 4:36. 


The result is that the projected time is now a course record.  It's 1:28:46 through 30km.  The last 5km were covered in 14:27.  That means the last 10km, from 20km to 30km, have been run in 28:53.


The projected time now is 2:04:51, and I have to say, it's likely to remain this quick.  Will we see a sub-2:05 in London to go along with Boston's sub-2:06?

Women 40km

The decisive move in the women's race has just been made - Shobukhova has gone clear.  Abitova managed to catch up to the leaders, which suggests that the pace dropped off.  As I mentioned, she was the barometer, and she is telling us that the pace dropped.  In response, Shobukhova has gone clear, and she is about to add London to Chicago, and cement her status as the top female marathon runner in the world.

Men 32km

Still Kirui and Kebede.  They're racing very hard, the pace is still high.  It's incredibly aggressive running.  I wonder if Wanjiru and Tadese and Kibet will even finish?  Another disappointing marathon for Tadese.

Women 41km

Shobukhova is well clear, on her way to a PB in the marathon.  She looks on for a 2:22 something.  She has been the class of the field today, always in control.  She was the first to take the lead when the pacemaker dropped out, and given her finishing speed, that would have been a concern to the other women - if she was confident enough to lead that early, then it was always going to be tough to beat her.

Women's finish

Liliya Shobukhova in 2:22:04 (unofficial).  The pre-race favourite has delivered in a new personal best.  Inga Abitova finishes second, a surprise name, and Mergia Aselefech in third.

And now, as expected, we'll get a good five minutes Mara Yamauchi coming in to finish in a time of 2:26 or even slower.  Meanwhile, the men's race continues, but let's watch Yamauchi finish outside the top 10.

Men 34km

Kebede is clear!  This is the decisive move in the men's race, and yes, folks, we missed it while waiting for 11th in the women's race.


In any event, Kebede is clear, with about 10 seconds on Kirui, who is fighting hard to keep up, but Kebede is looking strong in front.  The 21st mile covered in 4:33, that was the move that Kebede threw to gap Kirui, as we cut back to watch more women's finishers.  Is this 12th or 13th?  A spectacular finish for 12th, while Kebede and Kirui labour their way to 4:33 miles behind.  

Men 37km

Oh look, there is a men's race after all.  Kebede is clear, Kirui about 15 seconds back.  So the initial gap is now holding somewhat, but Kebede is looking well in control.  Back to the women's finish line, just in case we miss the athlete finish in 14th.  The men's winner is certainly not as important.

Men 37km

Kebede is on course for something around 2:05, which at halfway seemed unlikely. he has slowed somewhat, running 4:51 and 4:55 for the last two miles.  His PB, recall, is 2:05:18, set in Fukuoka.  South African woman, Tanith Maxwell has just finished in 2:34. 


18th now finishing.  I am thankful that the men's race is not closer.  At this stage, we're only missing the fastest men's performance ever.  Imagine there were five men together and the surges were being thrown.  Now it's 19th, really thrilling this.

Men 38km
The men are at 40km.  I'd guess that Kebede is still leading with Kirui in second.  But with even more excitement, I can tell you that Wilkinson has just finished, and then Docherty, in 2:38:10.  And now Harrison, and then I'm sure another five or six women in around 2:40.

If you're wondering who cares, then you're quite right.  So am I.

Men 39km

Back to the men.  The last mile in 4:46 and Kebede has the race in sight now.  He has perhaps 10 minutes to run, and having come second last year, he's going one better now.  The gap to Kirui is growing steadily, it's now about 20 seconds, and this is going to be the biggest victory margin in London in many years.  


Kebede is tired, he's hanging on, but I think less than everyone else.  It's been a bizarre race - "only" 63:10 to halfway, and then a huge explosion with successive 5km splits of 14:26 and 14:27.


I must confess that I'm surprised that it opened up like it did.  The surge was fierce, yes, but given the quality of the field, I expected more men to survive, even at that pace.  The second half will be significantly faster than the first, looking at about 62 minutes, perhaps a tiny bit faster, which is of course incredible running.

Men 40km

Meanwhile, back in second, Kirui is paying for the earlier surges, and it's Emmanuel Mutai who has moved into second.  The pace is slowing dramatically, as 40km was reached in 1:58:41.  That gives us a last 10km of 29:55, and those are times for Kebede.


The gap to second is just under a minute - 59 seconds, to be exact.  Which means, of course, that Kirui has covered the last 10km in 31 minutes.  Kirui may not even hang on for third, as he has only 20 seconds over Gharib, and he is finishing very slowly.


For Kebede meanwhile, the projected time is 2:05:12, which means that the course record now requires an increase in pace before the finish.  I don't think it will happen.

Men finish

Kebede wins, one second slower than his 2009 performance - 2:05:19.  It's the biggest victory margin in London for some time, we're so used to seeing sprint finishes and groups of three or four men head into the last 2 km together.


This, by comparison, was a solo effort, as Kebede managed to survive a fierce middle part of the race to emerge its champion.


Mutai has finished in second in 2:06:23, just over a minute back, and Gharib of Morocco has come third.  Bouramdane, also of Morocco has finished fourth, and Abel Kirui, who was the only athlete to follow Kebede's surge at about 35km, ended up fifth, having endured a terrible final 5km, his wheels really coming off after a brave attempt at challenging the small Ethiopian.


A real race of attrition - the first half was run in 63:10, the second in 62:08.

Ross 

58:23 Half marathon world record

Tadese runs 58:23 to break Wanjiru's world record

The big running news of the weekend was that Zersenay Tadese, the Eritrean former World Cross-country champion and multiple world half-marathon champion, delivered on his promise to break the half-marathon world record in Lisbon.

His time, an amazing 58:23, breaks the old mark of Sammy Wanjiru, the undisputed number 1 marathon racer in the world and sets up what should be a great showdown in London in just over a month (assuming Tadese goes ahead and races it, as he has suggested).

The London Marathon will also be a chance for some redemption for Tadese - he made his debut there, to much hype as the next big thing in the marathon, but he failed badly, dropping off the lead group early and failing to finish.  There is of course no guarantee that a super-fast half-marathon predicts a great marathon, and if anything, there may be concerns that he's too fast at this stage.  With a month to go, Sammy Wanjiru last year ran a mid-61 minute half-marathon and then dominated the Chicago Marathon.  So for Tadese to maintain the form he clearly has in Lisbon will be a huge challenge, and one of the fascinating sub-plots of the 25th April race, which promises to be one of the greatest ever. 

Tadese's times - solo effort of 27:40s for 10km

To put Tadese's performance into perspective, he reached 10km in 27:53, shedding the pacemakers at the ninth kilometer.  He then sped up to run the next 5km in 13:40 (15 km time of 41:33).  The next 5km split in 13:48 gave him a world record of 55:21 at 20km (30 seconds faster than Gebrselassie's old mark).  He brought the final 1.1km home in just under 3 minutes to eclipse Wanjiru's 3-year old record.

It was an amazing performance, for its consistency of pacing, and the fact that he ran it alone for the final 12 km.  Tadese has always been a favourite of mine, and he got some air-time back in 2008 when a scientific paper published his running economy - it was reported as 150 ml/kg/min, which is the lowest ever reported.  There were some theoretical problems with that paper, but the implication was clear - he'd be a fearsome runner over the roads. 

His track pedigree wasn't poor, of course - a few silver medals over 10,000m in some magnificent races against Bekele, who he really pushed to the limit on a few occasions.  But his territory always seemed to be the roads - absolutely dominant at the half marathon world championships, his future was always likely to come in the marathon.  And now, with this performance, all eyes will be on his return to the longer distance in London, and possibly beyond.  He is without doubt a potential world record holder, perhaps the next man to break 2:04.  With the kind of front-running he delivered in Lisbon, and the known front-running capabilities of Wanjiru (think Beijing, London and Chicago), a fast time in London seems assured. 

Gebrselassie bails in New York

Other racing news of the weekend is that Haile Gebrselassie was handed a rare defeat in New York, during the NYC half-marathon.  The world record holder over the marathon had already lost one record (20km, to Tadese), and just before 15km, he pulled up while in the joint lead with Peter Kamais, holding his chest.  He started again, but then stopped for good, checked into the medical tent and returned to the hotel.  In his absence, Kamais went on to win in a respectable 59:53.

There's a lot of chat about this on the running forums of the world, which is invited by Gebrselassie's approach to his running these days.  Very selective and very focused on times, which has meant that he hasn't raced the likes of Lel, Wanjiru, Kebede at the marathon.  Frustration and desire to see this race, particularly when Gebrselassie himself talks about the value of the Olympic Gold medal having pulled out of the Beijing Marathon and then breaking the world record a month later, leaves many feeling "cheated".  As a result, when he does enter a "race" (a debatable term for the NYC half-marathon - Kamais ran well, but it was expected to be a procession for Geb), and loses, it only re-inforces the perception that Gebrselassie is now a clock-runner, and unable to compete in a race.

I think that's a little harsh, because for a decade he was the greatest runner in the world.  And part of me accepts that he's earned the right to earn big money racing the clock in races of his choice.  However, I can't help but notice that he has never raced head to head against a top-ranked marathon runner and won, with the possible exception of Duncan Kibet last year, who was just poor.  Geb's marathon wins have all been clock efforts, his failures coming in London, with the strongest field by a long way.

Also, I must confess I'm tired of excuses from Geb after every failed attempt.  In London a few years ago, he missed a water station.  Then a year later, it was because the rain had made the cobbles slippery.  Then it was too cold, or too hot.  And it's always windy.  Beijing was too polluted, and the bed was uncomfortable in Dubai earlier this year, causing him to sleep badly.  Now, in New York, the lead vehicle kicked up too much dust, making the air difficult to breathe.  Geb may well have asthma, granted, but sometimes you're just not good that day.  One excuse after the other for Gebrselassie in the last few years and it's all becoming a little tired.

In any event, let's see what unfolds over the next month - Paris kicks off the Majors on April 11th, followed by Boston and then London, and we'll be covering it all for you!

Ross