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Tuesday, March 11, 2008

The Beijing Olympics: Pollution and performance

The Beijing Marathon - Pollution and Performance

Yesterday bought the sensational news that Haile Gebrselassie had made the "99% sure" decision to withdraw from the Olympic Marathon in Beijing and rather enter the 10,000m event.

His reason? The pollution, combined with his asthma, the heat and the humidity in Beijing posed a risk to his health, and he did not wish to compromise his chances in the 2012 London Olympics, or his ambition to run a 2:03 Marathon in the future.

Gebrselassie is a great athlete, maybe the greatest ever, but this story has a bizarre sound to it. For one thing, to make a decision now based on a race he hopes to run in four years' time, when there's even less chance of being competitive (he'll be 39, at the end of a career that has lasted 19 years!) does not seem a very sound one.

Secondly, it's highly unlikely that running the marathon in Beijing would affect his health in the long term. What it might do (and we'll get to this later) is affect his performance in the short term! That is, he might not have a very good race, perhaps, and worst case scenario, he'd be forced to bail from the race with breathing difficulties. But to suggest that his marathon running future is at stake is a little extreme.

Third, the pollution in Beijing is something of an unknown quantity, in that no one can say with any certainty how it will affect performances. To make a decision like this, fully 5 months out from the Olympics, seems to be jumping the gun a little. However, since we only know what is reported in the media, any speculation as to the process he followed (that is, consulting experts, visiting and trying to run in Beijing etc.) would be pretty wild. So instead of speculating wildly, I thought it better to dig up some information on the Beijing Marathon and see if it might be a guide as to what we could expect.

Performances in the Beijing Marathon - are they a guide to what we can expect?

This morning, I received an email from Amby Burfoot, providing a link to a really great site for statistics and marathon information.

The site has records on the Beijing Marathon, which is run every year in October. Some of these statistics are shown in the table below:

So, of interest is that despite not attracting a world class field of sub-2:07 men and 2:22 women, the times in Beijing (in October, at least) are quite decent - a 2:11:00 seems pedestrian compared to what we've seen in recent times in London, Berlin and Chicago, but it's by no means a disaster, particularly considering the relative weakness of the field. The worst performances in the last 12 years, incidentally, are more likely due to weak fields than any weather conditions, because in 2000, when the men were particularly slow, the women's winning time was 2:26, which is reasonable, and close to the overall average. Similarly, in 2006, when the women were slow, the men's race was won in 2:10:36, suggesting that conditions were not too hostile for fast times.

Speaking of conditions, what do we expect of Beijing?

Admittedly, the weather in October changes between August, when the Olympic Marathon takes place, and mid-October, when the Beijing Marathon is run. The weather stats are shown below:

The change in minimum temperature is particularly marked, I was surprised at how large it was. That 13 degree difference would of course have a profound effect on performances. Similarly, the change in relative humidity is significant. So the environmental conditions, it would seem, are a very real factor. But then we've known that all along, and it's going to be no hotter in Beijing than it was in Osaka last year for the World Championships, where times were slower, but it certainly was not impossible to run. And then of course, this is an issue mainly about pollution, not heat. The above racing performances seem to suggest that the pollution in Beijing is not so bad that it slows athletes down profoundly. Then again, one might argue that these athletes don't have asthma, as Gebrselassie apparently does...

The comparison between the Beijing Marathon and the Olympic Marathon therefore probably leaves us with more questions than answers! The two big unknowns, of course, are:

  1. What is the pollution level in August compared to October?
  2. How much does pollution, heat and humidity affect the very best elite athletes?
If anyone out there has access to pollution statistics in Beijing, please let us know! It would be interesting, as one commenter noted in the previous post, to compare London to Beijing. Again, this would serve only to provide some level of numerical comparison, just as the comparision between October and August does, because to actually predict performance implications based on this is not quite as simple as one might have hoped!

I'm sure there's a lot left in this story, and certainly in the pollution in Beijing story. We'll follow its developments!



Alan said...

don't forget seasonal wind direction and speed trends overlaid on a map of heavy industry ;-)

Hammstah said...

Wonderfully written, ended it with the right questions to be asked.

Anonymous said...

If the air is unbreathable for athletes, what makes it breathable for China's own citizens? And why haven't they had the same concern for their own people's health?! How does China's pollution effect surrounding countries, let alone the world.

I suppose the Olympics has been an eye opener to China. If they can successfully bring their pollution levels down, especially with them starting so high, maybe the rest of the world should follow in their footsteps for cleaner air. Granted, China is taking drastic measures, but if the rest of the world were to use their ideas in small doses, slowly everywhere would be better.


Ross Tucker and Jonathan Dugas said...

Hi Julia

The air in Beijing poses a major problem for the citizens. In our second article on this topic, written last year in November, we actually wrote about some of the things that it affects in Beijing.

For example, on some days, the visibility in Beijing is down to 50m because of the pollution, and it is so bad, that they have to postpone or delay flights.

It's also been reported that children and elderly people are warned to stay indoors, and that people who have to be outside must wear protective face masks! So it's certainly not optimal or breathable - it's just that they have no alternative. And from what I've seen and read about the way things are going in China, the people's health is the least of their worries - 11% economic growth, and billions to choose from, there isn't much the people can do to change things in the "machine".

You can read this post at:

Beijing Pollution concern

Also, they don't have ventilation rates in the hundreds of liters per minute. Remember, an elite athlete is going to be breathing at a seriously high rate and volume, the result of which is a total movement of air over the lungs that is far greater (as a rate) than any normal citizen. And this is the big mystery around Beijing - will it affect the athletes?

Having said this, I take your point, and hope they do sort it out. But honestly, if it's as bad as people are suggesting it will be, then the Olympics might well take the athlete's breath away!


N.N said...

Clearly Geb's reading this ;-), because now he says He does not want to rule anything out ... http://news.bbc.co.uk/sport2/hi/olympics/athletics/7292427.stm

Ross Tucker and Jonathan Dugas said...

Hi Lorenzo

I wish I could claim that he reads this blog and that we changed his mind!

But I must say I'm not surprised (I would be if he read this though!), because he's done this before - it was World Championships in 1997 I think, where he said he would not run because the track was too hard! If I remember correctly, he asked the stadium managers to pour water on the track, to soften it up! (it read a lot like this story you sent through!)

They refused, so he withdrew. The next thing you know, he's lining up in the final, apparently convinced by his federation to run!

So I'm not sure if it's a psychological game, or whether it's just his sense of humour, or if he genuinely means it and then can't say no when they ask him really nicely! But I hope he runs, for the sake of the Games and the marathon. I can't see them moving the marathon out of the city though...

We shall see...

Thanks for the link, will put up a reference to that shortly!


Anonymous said...

I have access to the air quality in Beijing but cannot provide it to the public, but there is no US city that comes close to the level of air pollution in Beijing.

With the focus on the air, I hope athletes do not forget about heat and humidity. One can acclimate to H+H, but not to air quality.

Exercising at moderate intensity gives one about the same dose of pollutants as sitting on a bench for 8 hours. (In Beijing). So it is not only the competition but the training while there. I bet you will see a lot of athletes flying in from Korea, Japan, Singapore, etc just before competition and maybe then even flying right back out between competitions.

Look for athletes using "gas masks" in training and walking around.
A question: is the course run in the Beijing marathon the same as the Olympic course? The latter is very flat. Not sure about the "regular" marathon.

Ross Tucker and Jonathan Dugas said...

hi Anonymous

Thanks for the post - interesting information - though I wish you could provide the data for comparative purposes!

The point about masks and flying in is correct - if you go to the previous posts we did on the pollution, we described that some teams are already doing this - the British will fly in, the Australians too. And probably more. Also, many have developed gas masks for use right up to the point of the race. So you're quite correct there.

Time will tell, but it might be the big talking point of the Games, unfortunately!


Anonymous said...

I think China's environmental record will increase dramatically proceeding the games, but the real challenge is in understanding whether or not their commitment to a "green" strategy will stay the course in the years after the Olympics.

If you want to read details read my post "An Inconvenient Olympics" at ecounit.com/blog. I make the argument that the Olympics will be the turning point for a global focus on conservation and "green" for the next decade.

Hope this adds to the discussion.



Ross Tucker and Jonathan Dugas said...

Hi Kent

THanks for the link - this is a topic we'll certainly be returning to, so I'll do a post closer to the time and get your blog in there with it.


Anonymous said...

On what scientific basis do you draw the conclusion that heavy pollution will not cause chronic health problems. There is a mountain of evidence that CO, SO2, NOx, O3 and particulate matter, whether in the short run or the long run, will cause disease. No one competing in these games is ethused about the conditions.

Ross Tucker and Jonathan Dugas said...

Hi Anonymous

I'm aware of that data, yes, but I feel you've taken it (or this post) out of context.

I do not believe that there is any evidence that a three-day exposure (arrive in Beijing 2 days before, then compete, then leave) will cause any such problems. The person may be affected during those three days, but within days of leaving much of the problem will be cleared, leaving no lasting effect.

I feel much has been made of the pollution and in the case of Gebrselassie, he's on record as saying he does not want to risk killing himself, which is extreme and untrue, as even the data would suggest.

So while i agree that most are not enthused, and I agree that they have reason not to be excited about breathing the air, there is a vast difference betweeen the problems caused by the pollution during the exposure and long term effects as a result of a few days worth of exposure. So I disagree!


Anonymous said...

World Development Indicators 2006 - Air pollution: http://siteresources.worldbank.org/DATASTATISTICS/Resources/table3_13.pdf

Thanks for providing us runners with a great website!