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Tuesday, April 22, 2008

Spring Marathon season

Wrapping up the spring marathon season - a Kenyan season, but will the Olympic Games be the same?

Yesterday's Boston Marathon brought the curtain down on the 2008 Spring Marathon season, and all eyes now turn towards the August Beijing Olympic Marathon. That will be followed by the Autumn racing season, consisting of Berlin, Chicago and New York, where hopefully, we'll see more world-class racing performances.

Because of the proximity of the Olympic Games, the Autumn races in October are more likely to feature the "could have beens", an opportunity for the fourth, fifth and sixth best runners to show what their federations might have missed, particularly in the case of Kenya. The Berlin race will almost certainly also feature Haile Gebrselassie, who looks set, I believe, to attempt the world record there, unless he changes his mind about Beijing Marathon participation.

A Kenyan Spring: The world's roads belong to Kenyan men

However, looking back over the last month's races, without a shadow of a doubt, the month of April, and the world's roads, have belonged to Kenya. Of the four marathons we covered (Paris, London, Rotterdam and Boston), Kenyan men claimed three titles, missing out only on the Paris race, which was won by Tsegaye Kebedi in impressive fashion. You can read our analysis of the World Marathon Major races by clicking on the "Marathon analysis" tab on the top of our page (you'd have to visit the site, in case you're getting this as an email).

But it was the manner of the Kenyan dominance that stood out. On Sunday 13 April, THREE Kenyan men broke 2:06, two in London, one in Rotterdam. They also placed fourth in London, took out seven of the top 10 places in Rotterdam, and then Robert Cheruiyot won Boston with a dominant, front running performance yesterday. Martin Lel, Sammy Wanjiru and Robert Cheruiyot are a ferocius trio, and surely, will be selected for Beijing. The heat may pose a problem (discussed below), but on form, they are very, very difficult to beat, given what we've seen over the last ten days.

So all is good in the world of Kenyan marathon running. This comes three weeks after their officials were ready to hit the panic button after a very disappointing showing at the World Cross Country Championships, where they failed to win a single title, being completely overshadowed by the Ethiopians. However, that is another story, one which I'll look at in the coming weeks, with an eye on the track events in Beijing. For now, however, world marathon running is very much a Kenyan affair.

Will the Olympics deliver the same results for Kenya? The potential of a "meltdown" in the Beijing heat

So quite rightly, Kenyan officials and fans will be expecting gold come Beijing. On paper, and on form, they have three out of the top four marathon runners in the world, men who have shown the ability to get the training and performance right on the day, along with ability to produce astonishing finishing kicks (Martin Lel - 60 second final 400m ability) and aggressive front-running displays (Robert Cheruiyot, solo running over Boston's hills). So, no apparent weakness then?

Well, not quite. There is the small matter of the heat and humidity in Beijing. And the reason this is all relevant is because no one really knows how these athletes will be affected.

A false perception that heat favours Africans?

There is a perception, certainly among the non-African media, that a hot race favours the Africans. And ordinarily, this would be so - they do train in Equatorial climates, after all, where summer temperatures are regularly in the 30's, with high humidity! However, it becomes very interesting to consider what happens in Kenya during the month of July, which is when the major training phase will take place in Kenya.

There is an important assumption to be made first, however. This assumption is based on my own personal interaction with scientists and coaches who have worked with the top Kenyan athletes, so I believe that it is reliable, though admittedly second-hand:

That is, most of the Kenyan athletes will not be leaving their normal training base to do any heat adaptation training in the lead up to Beijing. The reason, according to scientists at the Kenyatta University in Nairobi who we in Cape Town have done some work with, is that the athletes prefer the familiar environments and the single-minded focus these bases provide them with. So rather than adopt the approach of a Paula Radcliffe, and the US Olympic team, who are planning training camps in the hotter European climates, many of Kenya's best will remain in their high-altitude camps right until the Games.

This has major implications for their ability to adapt to the heat. Because contrary to popular belief, Kenya is nowhere near hot enough to acclimatize during the winter months of June and July! Cold is of course a relative term, but if you take a look at the historic weather data for Kenya in July, you'll see that in Eldoret (perhaps the most famous training base), the average peak temperature is ONLY 20 degrees celsius (69F), and the typical morning temperature is 10 to 11 degrees Celsius (52 F). Remember that Eldoret is at altitude (2,100m), and so it's neither hot nor humid there in the winter months.

This means, of course, that a Kenyan training in Eldoret during June and July has zero exposure to temperatures likely to be encountered in Beijing. For the record, the average daily temperature in Beijing in August is expected to range between 20 and 30 degrees, with a humidity in excess of 70%. Those are seriously challenging conditions, and if an athlete heads into that situation unprepared from a heat-physiology perspective, the effects will be severe.

The Ethiopian approach to Osaka, and Kenya's options

What is interesting to consider is the difference in approach taken by Ethiopian athletes in the build-up to the IAAF World Athletics Championships in Osaka last year. Osaka, incidentally, is very similar to Beijing - hot and humid. I know that the Ethiopians, who are the same as the Kenyans in that they choose to stay in the country to prepare for the major races, actually brought in expertise that included providing access to a heat chamber before they went to Osaka.

So, given that Osaka was going to be hot and humid, the Ethiopians made use of a chamber which effectively brought the heat to them. They did training sessions which simulated Osaka conditions, and it's likely they'll be using the same in preparation for Beijing. This was a highly efficient technique since as little as 60-90 min per day in the heat chamber will stimulate the physiological adaptations that will enhance thermoregulatory function in the heat. These runners are likely already running twice a day, so once in the chamber should not have impacted their high-quality efforts.

Whether the Kenyans will adopt a similar approach remains to be seen. From a physiological point of view, it is absolutely crucial that any athlete who wants to be competitive in Beijing be adapted to the heat.

It doesn't matter how good you are, how dominant a marathon runner, if you are unfamiliar with the expected heat in Beijing, physiological function will be compromised when you are first exposed to the heat, and it takes a minimum of five days of exposure to start to see any adaptations.

The scientific evidence on this is very clear - it takes between 5 and 8 exposures to hot and humid conditions before the body has made most of the adaptations and is able to keep its temperature down. The problem for the Kenyan runners, then, is that unless they figure out a way to expose their physiology to the Beijing heat and humidity, they will be entering the race "cold". This has happened before, and there's a chance it will happen again.

If it does, then don't be surprised if a relatively unknown athlete comes in and wins a surprise Gold medal. It is for the reasons explained above that I believe that Sammy Wanjiru, thanks to his familiarity with the Far East, and possibly the fact that he'll be based in the East during his build-up, is the bigger favourite, despite the fact that I believe that Martin Lel is the world's greatest marathoner today. Lel, all things being equal, wins any marathon he runs in. Unfortunately, things are rarely equal, and the heat is the great leveler. Kenya, for all its dominance over the roads of London, Boston and Rotterdam, may yet find itself neutralized by a failure to prepare for the heat in Beijing.

As the Olympics draws nearer, this issue of heat will become much more relevant. We will certainly bring you all the insights and explanations, including a full series on heat physiology and acclimatization, and also hopefully some inside information on what the Kenyans and Ethiopians are doing!

Ross

7 Comments:

Ohionative said...

Hello, sorry for the non-related comment but I was hoping that you guys might have some information on the nutritional practices of elite athletes. I have read your series on hydration and your quick post on caloric intake for a tour cyclist. Both were extremely informative. I feel as though a good discussion could be brought out on the diets of elite runners and athletes in regards to: during training, leading up to a race, DURING A RACE, and post race. There are currently so many "food" products for athletes and it seems like there is not very much good scientific literature about these products (outside of the products websites). Any information on this topic would be awesome.

I really enjoy reading the blog and have found it amazingly informative. If you're ever in the San Francisco area you have a running guide for some of our great trails.

Nathan Y

vikram said...

another suggestion, there are posts on marathon analysis as well as some cycling and swimming related discussions. have you ever considered analysis of ironman events ? i would love to read both your perspectives and analysis of such events.

jorge pereyra from Uruguay said...

Something from the cience about Hot and humudity.

Superior performance of African runners in warm humid but not in cool environmental conditions

Frank E. Marino,1 Mike I. Lambert,2 and Timothy D. Noakes2
1School of Human Movement Studies, Charles Sturt University, Bathurst NSW 2795, Australia; and 2MRC/UCT Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town 7725, South Africa

Submitted 5 June 2003 ; accepted in final form 27 August 2003

The purpose of this study was to examine the running performances and associated thermoregulatory responses of African and Caucasian runners in cool and warm conditions. On two separate occasions, 12 (n = 6 African, n = 6 Caucasian) well-trained men ran on a motorized treadmill at 70% of peak treadmill running velocity for 30 min followed by an 8-km self-paced performance run (PR) in cool (15°C) or warm (35°C) humid (60% relative humidity) conditions. Time to complete the PR in the cool condition was not different between groups (27 min) but was significantly longer in warm conditions for Caucasian (33.0 ± 1.6 min) vs. African (29.7 ± 2.3 min, P < 0.01) runners. Rectal temperatures were not different between groups but were higher during warm compared with cool conditions. During the 8-km PR, sweat rates for Africans (25.3 ± 2.3 ml/min) were lower compared with Caucasians (32.2 ± 4.1 ml/min; P < 0.01). Relative rates of heat production were less for Africans than Caucasians in the heat. The finding that African runners ran faster only in the heat despite similar thermoregulatory responses as Caucasian runners suggests that the larger Caucasians reduce their running speed to ensure an optimal rate of heat storage without developing dangerous hyperthermia. According to this model, the superior running performance in the heat of these African runners can be partly attributed to their smaller size and hence their capacity to run faster in the heat while storing heat at the same rate as heavier Caucasian runners.

This a different point of view

regards

Dr. Jorge Pereyra

Stan Silvert said...

Why the fancy heat chamber? Doesn't training in a sweatsuit have pretty much the same effect?

Come to think of it, is there any evidence that heat acclimatization has a positive impact if you are training for a race in "normal" weather? The Japaneese seem to think so.

Stan

Adeel said...

It's amazing that Kenya has Kipsang as an alternate on the team, and he has run 2:05, along with 2:06 twice.

Bulhão Pato said...

Hi guys,

Let me start by applauding your fantastic work in this blog. Great reading. It's a must every week to come here and read the latest on sport's technology and science.
If I may, I'd like to propose a topic: as you may know, the next Champions League final (in soccer, that is) will be played in the Luzhny stadium in Moscow, where England recently lost its hopes of qualifying for the Euro'2008. Well, the Luzhny stadium has an artificial turf, as natural grass doesn't resist to the Russian winter. UEFA made sure that this final should be played in natural grass, but I'm wondering what are your thoughts on artificial versus natural grass. What kind of impact does the artificial surface has on the human effort?

Take care.

jorge pereyra from Uruguay said...

Something from the cience about Hot and humudity.

Superior performance of African runners in warm humid but not in cool environmental conditions

Frank E. Marino,1 Mike I. Lambert,2 and Timothy D. Noakes2
1School of Human Movement Studies, Charles Sturt University, Bathurst NSW 2795, Australia; and 2MRC/UCT Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town 7725, South Africa

Submitted 5 June 2003 ; accepted in final form 27 August 2003

The purpose of this study was to examine the running performances and associated thermoregulatory responses of African and Caucasian runners in cool and warm conditions. On two separate occasions, 12 (n = 6 African, n = 6 Caucasian) well-trained men ran on a motorized treadmill at 70% of peak treadmill running velocity for 30 min followed by an 8-km self-paced performance run (PR) in cool (15°C) or warm (35°C) humid (60% relative humidity) conditions. Time to complete the PR in the cool condition was not different between groups (27 min) but was significantly longer in warm conditions for Caucasian (33.0 ± 1.6 min) vs. African (29.7 ± 2.3 min, P < 0.01) runners. Rectal temperatures were not different between groups but were higher during warm compared with cool conditions. During the 8-km PR, sweat rates for Africans (25.3 ± 2.3 ml/min) were lower compared with Caucasians (32.2 ± 4.1 ml/min; P < 0.01). Relative rates of heat production were less for Africans than Caucasians in the heat. The finding that African runners ran faster only in the heat despite similar thermoregulatory responses as Caucasian runners suggests that the larger Caucasians reduce their running speed to ensure an optimal rate of heat storage without developing dangerous hyperthermia. According to this model, the superior running performance in the heat of these African runners can be partly attributed to their smaller size and hence their capacity to run faster in the heat while storing heat at the same rate as heavier Caucasian runners.

This a different point of view

regards

Dr. Jorge Pereyra