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Friday, October 30, 2009

New York Marathon Preview and predictions

New York, New York: The final swing on the 2009 Marathon calendar

Sunday sees the final marathon of the Fall season in the World Marathon Majors in New York, and it's one of the most exciting fields of the year (only London matches the men's field for competitive depth). So I'm interrupting the series on coaching and science to pull out the crystal ball and look ahead to the race, where a course record, at least on the men's side, seems a real possibility.

New York is arguably the toughest course of the Majors. At least, it's record times suggest this, with a men's record only just inside 2:08. Back in 1989, Juma Ikangaa ran 2:08:01, and that would last for 12 years before Tesfaye Jefar nudged it down to 2:07:43, which stands are the current record.

Given that London, Berlin, Paris, Rotterdam, Amsterdam, Dubai and Chicago all have course records under 2:06, that 2:07:43 stands out. The twisting roads, short hills on bridges and around Central Park make NY a tough race. And a tough race can throw up surprise winners, as it has in the past.

Last year, Marilson Gomes dos Santos managed to claw back "Mr Second place", Abderrahim Goumri, in what was an exciting finish. Goumri looked to have the race won, but dos Santos hung on and then shot past him, eventually winning by a large distance. It was dos Santos' second win, his first came two years earlier, in a race where it seemed the big guns decided to let him go, and couldn't catch up. That was a surprise. 2008 was a surprise (of sorts).

Don't expect another surprise on Sunday
- dos Santos may be suited to NY, perhaps the tough course plays into his strengths, but I have a feeling that a top 5 is the best the defending champion can aim for. The way the marathon has leaped forward this year, I don't see a slow pace with surges, and I'm not sure that dos Santos is one to handle 2:05-intensity (even if the course turns this into a 2:07-pace).

The big 5

So then who to look out for? Well, three Kenyans, one Moroccan, and an American stand out as ones to watch.

The Kenyans are James Kwambai, Robert Cheruiyot and Patrick Makau. Neither Kwambai nor Makau have ever won a marathon. But Kwambai has twice broken 2:06 - once he accompanied Gebrselassie to 35km in Berlin (arguably contributing to a sub 2:04 time), and once he accompanied Duncan Kibet to the finish line in Amsterdam. On that occasion, he ran 2:04:27, the third fastest in history.

The problem for Kwambai, apart from not having winning momentum, is that he has a super fast half marathon very recently - as Lets Run.com have pointed out in their preview, a very fast half weeks before a marathon is often a sign that the athlete was on the edge for too long, and hits the marathon just slightly over-done. Wanjiru, they point out, ran a 61:08 in the same race as Kwambai ran 59:08, about six weeks ago. As you know, Wanjiru went on to run 2:05 in Chicago. So either Kwambai is going to rip New York apart, or he'll struggle after 30km. Not that it's unheard of to run great marathons soon after great half marathons, mind you. Martin Lel has won the Great North Run only a month before winning New York, his time in the GNR always under 60 minutes. So it can be done. But that's Lel, not Kwambai, and the final 5km may tell on Kwambai if he's is over optimal shape.

Robert Cheruiyot is an interesting case - 18 months ago, he was a dominant force in the marathon. He won Boston by attacking at about 21km, and destroyed the whole field. He was a Major series champion, a four-time Boston winner, and without doubt one of the top 2 in the world (Martin Lel was the other). But age, injury and illness seem to have slowed him, and he has struggled. He was a late addition to the field, after the withdrawal of Paul Tergat, at the tenth hour, and the question is whether his form is good enough to compete. I have a feeling he'll struggle, and his time at the top may be at an end. However, he warrants a mention, because as I say, it was only 18 months ago that he was near invincible. It shows how rapidly things can change in marathon running.

Patrick Makau is also an unknown quantity of sorts. His half-marathon credentials are excellent, with a 58:52 performance earlier this year. And he did debut in 2:06:14 earlier this year. That's a frighteningly fast first outing, and even a slight improvement makes him a big threat. I pick him to come second - inexperience will still count against him - remember that Gebrselassie took a few attempts to sort out the marathon race, and so Makau may yet evolve into a great champion, but New York will be a step, not a leap, in that direction

Jaouad Gharib is the man to watch, however. The Olympic Games silver medallist had always been a championship type runner, but earlier this year, he made a step up and in London, mixed it with Wanjiru and Kebede to finish third in a new best time of 2:05:27. That time suggests that Gharib is on the way up, not down, despite his relatively long career (he was world champion back in 2003 and 2005). He followed Beijing up with a great London performance, and he comes into NY as the favourite, in my opinion, now that Martin Lel has withdrawn. The one problem for Gharib, in my opinion, is whether he is assertive enough to make the running. In Beijing and London, he tracked moves until he couldn't, but ended up outlasting everyone but Wanjiru (and Kebede). Will he be assertive enough to throw it down in the Park? Time will tell...

Finally, we have Ryan Hall, the great American hope. Hall has been training well in Mammoth Lakes, I believe - I was at a symposium in Colorado Springs recently where his coach Terrence Mahon was a speaker, and it was revealed that Hall was regularly completing 18 mile training runs at about 5:00/mile pace at 7,500 feet (2,300m). That puts his NY preparation ahead of what he was doing for Boston earlier this year, so his condition is apparently good (as far as training reports can be relied upon, of course). He has some good half marathons in him, and is full of confidence, according to a RW interview with him recently.

So can Hall do it? The simple answer is yes, of course, because he's up at the level required of a champion marathon runner with a 2:06:17, which is the 4th best in the field. In New York, the difference between a 2:05 PB and a 2:06 PB is not as large is it is in say, London or Berlin, and Hall knows and enjoys the Central Park section of the race. But, as Letsrun have pointed out, his best is only 25th in history, such is the explosion in sub-2:06 times recently, but Hall is certainly a contender. Third in Boston earlier this year, behind an incredible run by Deriba Merga, suggest that Hall will at least be involved until the final few kilometers. So he can win, but I suspect it may be just too challenging in those final kilometers, and he'll finish third again.

So what does the podium look like, to sum up?

1. Jaouad Gharib - 2:07:22. Yes, the course record will fall, because 2009 has thrown marathon running into the new era, and NY will be pulled along with it. Expect a first half of around 1:03:10, with surges causing a slight slowing in the last half. Hendrik Ramaala of South Africa will feature in the early surges after halfway, but after 32km, he'll drop steadily off the pace.

2. Patrick Makau - he'll be with Gharib until the 40km, and will then slip back, finishing around 20 seconds down.

3. Ryan Hall - expect Hall to make the move that splits the race, at around 32km. A large group will be whittled down to four or five, and Hall will last enough to claim third, in a strong run, just outside 2:08.

Women's race: Paula all the way

The women's race is much easier to call. A spate of withdrawals has weakened the field considerably, and only Selinah Kosgei, this year's Boston champion, stands as a reasonable threat to the dominant runner over the last decade.

Paula Radcliffe's races are also pretty easy to anticipate - she runs hard, setting a tempo that is simply too quick to hold onto, and the field is cut one-by-one, until she's either all alone (as is normally the case), or one or two hang one, as was the case in a memorable race against Gete Wami back in 2007, where she won her second title.

This year should follow the former pattern, with Radcliffe pulling away to win relatively comfortably. The next question is whether she can get the course record, the 2:22:31 of Margaret Okayo. Radcliffe is a three-time winner in NY, with a best time of 2:23:09, back in 2007 during the Wami race. She's just recovered from a bout of tonsillitis, and with Radcliffe, you never know what injury hassles may have affected her training. She's been close to marathon shape for a long time, almost running the World Championships marathon in August, but deciding to withdraw late on because her form wasn't quite where she wanted it.

Then she withdrew from her home World Half-Marathon championships thanks to tonsillitis, so she's clearly been hovering on the brink of racing shape, but for a few problems. They won't affect her victory, but they might just prevent the record.

So I'll predict Paula to win, but just outside the record - 2:22:49.

Selinah Kosgei in second, somewhere in the mid 2:24 range.

Coverage of the race

And that, as always, was my crystal ball prediction! Tongue-in-cheek, of course!

For race coverage, as has been the case for the Majors, join us on Sunday, for live splits - not the 1km splits like for Chicago, unfortunately, but five kilometer times, if possible!


Monday, October 26, 2009

Coaching and science: Asset or liability

Coaching and science: What's the big deal and who cares for the science?

As promised, today begins a series of posts on coaching and science, and how the science can be, should be, and sometimes is, and often is not, applied to athlete preparation. Obviously, it comes with an endurance focus, but there's no reason why sprint coaches and team sport coaches can also not glean some information from this.

This is a series that was inspired by my visit to the US Olympic Center in Colorado Springs. I was lucky enough to be invited there by Prof Randy Wilber of the USOC, who had organized a symposium on altitude training. The symposium brought together scientists, coaches, athletes and mangers from 22 different countries, and included 32 Olympic athletes, and numerous sporting codes, Summer and Winter Olympics among them.

An uneasy marriage?

So it was a symposium that created the perfect platform for the marriage of science and coaching. Yet, two days later, and I don't know that too much had been gleaned from the science part of the symposium. At the risk of dismissing its value, the coaches probably gained enormous value from other coaches' presentations - Bob Bowman (Michael Phelps' coach) would have heard some valuable tips from Terrence Mahon (Ryan Hall and Deena Kastor, among others), and vice versa, but I dare say that the science would not have changed the way any of the coaches are approaching altitude training for their athletes. They already had a strategy, and I doubt whether the science showed them anything to improve or change it.

And this is a typical problem - coaches have historically done things well in advance of the science proving (or disproving) that they work. The famous running coach, Arthur Lydiard, was once reported to have said that the coaches already know what works, and the scientist's job is to tell them why it works! Now, that's not always true, because often, coaches do the wrong things, or they fail to do things that would help, or they are unaware of methods to improve performance. So it's not quite as simple as saying that science chases after the truth long after the coach has discovered it. Lydiard said this long before much of today's technology was available, and perhaps his view would now be different

But the eternal questions remain:

  1. What value does science add?;
  2. How much science does a good coach need to know? and;
  3. Is the science sometimes more of a liability than an asset?
I believe that as sport gets increasingly competitive, there is no doubt that the effective use of science (and we'll explain what this means in the series) is the difference between turning mediocre into good, good into great, and great into world-champion. The question is, what is effective science, and how should it be applied?

One person's view: heart rate monitors + books = science

And co-incidence luck would have it, I woke up this morning to discover LetsRun.com's quote of the day was the following, from Steve Jones:
"What I do is make it simple," Jones, now a teetotaller, says. "There's no science in it – no heart-rate monitors. It's just running – running instinctively. Anyone who saw Steve Jones run in the Seventies, Eighties and early Nineties knew that he ran by the seat of his pants nearly all the time. You don't see that any more and that's what I'm trying to teach these guys. None of it comes out of a book. It all comes out of my own experience."
Quite clearly, Jones thinks that science is the sum of heart rate monitors and books. And no doubt, some will agree. I don't. My definition of science, particularly as applied to the coach, is far broader than this, and I dare say that Steve Jones applies a great deal of science to his coaching without even realizing it.

Our purpose and these questions

So what then does this application look like? To begin, the video below is an interview that I did with Training Peaks a week ago, in Boulder, Colorado. For those who don't know, Training Peaks make software to allow athletes and coaches to manage and monitor training. The management of data is, as I mention in the interview, a fundamental aspect of the scientific process applied to training. I'll describe this in a lot more detail in the next post.

If you've not seen Training Peaks software, I really do recommend that you check it out, because it offers so much value that if your big obstacle is managing your training (or that of your athletes), it might be the solution, particularly if you have a large group and you want to keep tabs on many at the same time.

However, in the interview, at around 5:40, Dirk Friel (Training Peaks Chief Marketing Officer, former pro cyclist) asks about coaching, and my answer is really the key to understanding what I believe to be the scientific value to coaching.

Also in the interview are some thoughts on how we began The Science of Sport, and some of the good stories of 2009, but that's really just for interest's sake - the real content is from 5:40 onwards!

Science is the process, not only the theory

To sum it up in a nutshell, there are really two aspects to science for the coach:

First, there is the theory. How the body adapts to stress, overtraining, environmental factors, diet, hydration, biomechanics, cardiovascular system and nervous system, and so forth. Steve Jones would call this the "book", and many coaches would be put off from looking it up, since this is the domain of the white-coated academic in the lab. The better coaches, in my opinion, seek to take from this theory and apply it, and we'll discuss that in more detail soon.

However, the second part of the science is, in my opinion, even more important. It involves the ability of the coach to engage in a scientific process. And what is a scientific process? It is the process by which you ask a question, design an 'intervention' (in this case, a training programme), create a hypothesis (for example, the athlete will run a 5km PB in three months), and then measure and collect data. If the data suggest all is on track, then the coach continues. If it suggests the athlete is not adapting, then the plan is changed, and a new intervention begun.

That's science. Coaching is the application of the same process as a scientist would follow if they wanted to test whether a transcription factor was involved in regulating the activity of a gene. There are differences, sure, but the process of measuring the athlete's response to the training, and then adapting the training to maximize the response requires the same system of thinking, and that is why the best coaches are also "scientific-minded". The interview above hopefully clears that up a little more.

So join us next time when we look more specifically at what scientific theory is valuable for coaches, and how this process should actually work. I think you'll find that good coaches do all of this already, and for them, the improvement in coaching ability comes from tiny adjustments, also made with some science behind them!


Deaths during running: Is exercise safe, Part 2

Running and safety continued - some comparisons, and the key point to the debate

One of the best things about this site is that often it is a source of information for me as much as I hope it is for you! And in response to last week's post about the safety of running, we've had some great comments and more information, which warranted a follow up. Also, I felt I should re-emphasize the purpose of that post, which was really a call to the media to change the view they project of running.

And most importantly, it was a message to runners out there to help them 'filter' out what is basically over-hyped reporting about deaths during running, akin to the "shark attack" phenomenon, where sensational reporting skews our beliefs over the relative safety of an activity (surfing in that case, running in ours). Perception does not necessarily equal reality, in other words, and the post was a call to question very hard what the risk of running is. If you do, you'll find that it's not nearly as high as is sometimes portrayed!

And now we have some points of comparison, thanks to you readers!

Host a marathon every weekend

First off, a study last year from the British Medical Journal took a rather creative (Malcolm Gladwell-esque) look at marathon safety. Canadian researchers compared the risk of dying in a motor vehicle accident with that of sudden cardiac death during marathon participation. Because courses are closed to traffic for larger races, it's possible to ask how many motor accident deaths would have been prevented as a result of the race, and compare this to actual deaths (thanks to Bengt, Tony and Amby for raising this one! As an aside, the author Redelmeier seems to be an expert on driving fatalities - another 2008 study published in JAMA is called "Driving fatalities on US presidential election days")

The diagram below summarizes the main finding:

So basically, the study found that the closure of roads for the major marathons prevented an estimated 46 deaths as a result of motor vehicle accidents. However, 26 sudden cardiac deaths were reported during those races (based on newspaper reports, it must be pointed out, and thus potentially a slight under-estimate). The relative risk - 35% lower when marathons happened.

And a final really important point - the authors have controlled for the accidents simply be relocated to other areas, and so marathon closures do not simply shift the site of the accidents. If you want the paper to check out their solid stats, please just let me know, as usual.

The author's conclusion is shown in italics above, but it was that "Organised marathons are not associated with an increase in sudden deaths from a societal perspective, contrary to anecdotal impressions fostered by news media."

Some numbers

Interesting that they picked up on the "impressions fostered by news media", which is basically the point of these last two posts. Interesting also that in 14 million hours, there were 26 deaths, which amounts to approximately 1 per 540,000 hours, a figure which agrees with that which our friend Amby Burfoot put forward in his comment to our last post. For a similar analysis, check out Amby's report on marathon deaths written last year, which is far more comprehensive than I've had time to do here - it's a big read, but if you're up for more details after this article, check it out.

This figure of 1 per ± 500,000 hours is also about the same as a (very) crude calculation would provide based on the information that about 6 deaths occur every year in the USA, and that about 3 million hours of running go into those deaths (this was all covered in the last post, if you want to read the numbers more).

My point, however, not covered by this study or the latest reports, is that marathon running hours are not limited to the hours of participation. There is substantially more time spent running in training, and by those who run but don't participate. If you factor all these people in, do the numbers change? Without quantifying training times, it may remain an unanswerable question.

These people, and their training, are the most important component of the debate, because they are most likely to be dissuaded from running as a result of the negative portrayal of running. Yet they are clearly, based on a large body of research by the likes of Paffenbarger (again, see the previous post), more protected than the sedentary population, and so should be hearing affirmation, not condemnation or warning for their choice to run. And if running in events that may have a risk of 1 death per 500,000 hours is the goal, then it too should be encouraged.

Comparing running with some other activities

To compare running a little better, have a look at the comments to the previous post, where you'll see some stats about how many deaths are caused by other activities. Smoking, for example, claims over 300,000 each year. Flu, 15,000, and car accidents, 20,000. Of course, the problem here is that these numbers don't indicate the 'exposure', or how many people spend how much time doing the activity. Smoking may simply be high because many people smoke, whereas 6 sudden deaths during running may be because hardly anyone runs.

Risk and exposure

So, for another comparison, I received data from a reader who had put together some stats on deaths per million hours of the activity. That piece can be read here, and the original article is here.

Admittedly, it's a little uncertain where this data were sourced, and in this field of epidemiology, that is crucially important. So with a proviso that the data is not "gospel", here is the summary list:

Deaths per million hours:

Skydiving - 128.71
General Flying - 15.58
Motorcycling - 8.80
Scuba Diving - 1.98
Swimming (presumably competitive) - 1.07
Snowmobiling - 0.88
Motoring - 0.47
Water skiing - 0.28
Bicycling - 0.26
Airline Flying 0.15
Hunting 0.08

Running? Depending on which number you believe, the risk during marathons is between 1.8 and 2 deaths per million hours, so it's around the same as scuba diving.

One problem - that doesn't factor in the health benefits, which I emphasized previously. Regular physical activity reduces the risk of cardiac disease and a host of other health problems, and so the risk is moderated by the benefit.

Most important of all - applying this dizzying collection of numbers to yourself

To end off (before we tackle some more enjoyable topics like coaching and science in the coming days), a word on applying this to you. I know I've thrown figures and numbers at you, and your head is probably spinning, so let's try to simplify this.

The reality, at the risk of sounding callous, is that people do die during running. A big race, with 30,000 runners, seems likely to experience such an event every 3 to 4 years. Put differently, between the six major marathons each year, there would be a sudden cardiac death each year.

People who are predisposed to cardiac death are more likely to die while running than while sitting on their couch. This is undeniable. But equally, people who run, including those who run marathons, derive enormous benefit from it - their health gains as a result of running are sufficient to over-ride habits like smoking in terms of overall risk of mortality (Paffenbarger, et al).

You can investigate whether you might be one of those predisposed, higher-risk people, but the problem, as we've discussed at length before, is that medical testing cannot currently identify all the people at risk. Some, certainly, and so medical screening, particularly if you are concerned, would be advisable.

Even in the absence of such 'confirmation', however, you still have a choice. With the risk at one death per 500,000 hours of running, and with the knowledge that running can improve your health, your choice is to remain sedentary and avoid that 0.8 in 100,000 runner chance, or you can run and benefit from the numerous positive adaptations you'll experience. It is a risk-management matrix, where running and remaining sedentary must be weighed against one another, benefits and risks understood, and a choice made. Your ability to manage the risks, by undergoing tests, by training and by adopting a healthy lifestyle, makes this choice far simpler than leaving it to guess-work.

And finally, for the media, physical activity should be encouraged, not 'demonized' with threats of death caused by activities like running. Sensational sells, but when it deters people from running, it becomes a problem. So some perspective, some affirmation and positive reporting would go a long way to fixing what is a growing problem of inactivity and obesity, subtly being driven by the media reporting. By all means, educate and inform people of how to maximize benefits, but let's not give a voice to those who view exercise as radical from the safety of their couches.


P.S. As mentioned, a series on coaching and the application of science starts tomorrow. Join us then!

Further reading:

Amby Burfoot, Editor-in-Chief of Runners World has done a comprehensive piece on safety of marathon running. I've tried to make this article (and the one before) more philosophical and directed at the media coverage, whereas his is full of information and 'hard facts'. But this is a great piece, and if you're up for more reading, this is a great read:

Amby Burfoot:

Thursday, October 22, 2009

Deaths during running: Is exercise safe?

Sudden death during exercise:  The media, risk and running

For those who have not heard or read the news, three runners died during the Detroit Marathon/Half-marathon last weekend.  All three were running the half-marathon, and were aged 26, 36 and 65.  The three collapsed within 16 minutes of each other during the race.  The timing, the wide spread of ages, and the fact that three deaths occurred in one race (which was not hot, I might add) have given the story 'legs', and it was even covered on CNN.

Whenever this kind of incident happens, there is debate and discussion around the safety of running.   It's always bad press for running.  It is a topic that pops up fairly regularly, and we've actually covered it in a fair amount of detail here on The Science of Sport.  I'm not going to go into enormous detail on sudden deaths during exercise again, but for those who are interested, you may like to read the following posts:

A general perception of safety

So as I said, I wouldn't ordinarily post on this topic again and in the case of the Detroit runners, I don't know the cause or any details, and so it would be wildly speculative to discuss specifics.  However, this latest incident, and the media reporting around it, reminded me of a thought I'd had while watching the NBC coverage of the Chicago Marathon about 2 weeks ago.

You may recall that Jonathan and I were in the control area, doing real-time pacing for the race, and also spent some time in the medical tent.  But it was watching NBC's coverage, that I was struck by the fact that the person who was interviewed the most during a 3 hour broadcast was the race doctor, George Chiampas.  On no fewer than four occasions, Dr Chiampas was featured in a two -minute interview, giving his thoughts on race hydration, race safety, post-race safety, recovery, training and so forth.  And while he answered the questions very well, it was clear that the 'safety/danger' of running was of utmost importance to the broadcaster.

It struck me that there is a very real perception among mainstream media in the USA (remembering I'm from South Africa and so normally unaware of this message) that running is a risk.  That is, viewers who watched the broadcast of Chicago and who were NOT runners would be left under no illusions that attempting to run a marathon is a dangerous task.  The "shock and fear" coverage, which implies danger at every turn, sends a clear message that if you run a marathon, you are taking a chance with your life.

And this unfortunate, because it ignores the whole other side of the argument, and does so with little to back it up other than infrequent and over-hyped incidents.  A thoughtful, balanced approach would cover two additional aspects:
  1. It would consider whether the risk of death during running is in fact greater than during any other activities, and;
  2. It would look at whether the average  runner (from recreational to the marathon) was deriving a benefit from running, and whether this person was in fact less likely to die than someone who chose to stay on the couch because of all these "life-threatening" risks.

Millions of hours invested, but even stats don't tell the full story

Then there is the statistical approach, which many resort to in cases like this.  I read in a report from Fox News that a total of 425,000 runners completed marathons in the USA in 2008, and another 715,000 completed half-marathons.

If you convert that to time, assuming that the average marathon and half-marathon time is 4 hours and 2 hours, respectively, then you can work out that a total of 3.1 million hours of running time goes into those races.  And this does not include the training, or the 5km and 10km races done along the way.  If you assume that the average person trains 2.5 hours a week for 3 months to run a marathon or half-marathon race, then you get a grand total of 34.2 million hours of training time per year for those runners.  The total running time for marathon and half-marathon runners in the USA per year?  37.2 million hours of running (and this is an underestimate, I must point out - it does not take into account the millions who spend an hour a week jogging in the gyms, or those who train but don't race)

So what is the frequency of mortality for these runners?  Fox News reports that about 6 deaths per year occur during races.  How many during training?  We don't know, unfortunately.  But the point I'm trying to make is that these deaths are rather less common than they may seem - one per million hours, perhaps?  One per three million hours?  Until that is quantified, reports that marathon running is dangerous are simply irresponsible, the result of a classic 'media-led knee-jerk reaction', where news reporting makes us over-estimate the prevalence of such events.  A classic example is shark attacks - they are exceedingly rare, but when they happen, they're so dramatic that they receive hyped-up media exposure and so we think they're more common than they are.  I suspect the same is true for running-related deaths.  (What would be great is to compare this number with other activities - driving your car, flying, playing other sports.  If there are any economists or actuaries out there who know this, please speak up!)

The real story - the benefit that the media don't report

But these stats don't tell the whole story anyway.  What you really need to ask is whether exercise adds up to a longer, healthier life, even taking into account what I believe is a tiny risk.  In other words, you need to look at the overall benefit of being active, and ask whether those who run are less likely to die than those who do not?  There is no doubt, based on the evidence, that exercise reduces the risk of morbidity (disease) and mortality (death).  One of the most famous names in exercise science and health is Ralph Paffenbarger, and he demonstrated pretty clearly that increasing exercise was associated with decreased risk of disease and death.  The most famous study is perhaps this one, his Harvard Alumni paper.

Paffenbarger went so far as to show that people who exercised AND smoked, were less at risk than those who didn't smoke, but didn't exercise either.  So, if you want a debate about the benefits of exercise (and I include running here), the real issue is whether those three deaths, and then dozen or so that seem to happen each year during running, outweigh the fact that those same people, if inactive, would have a lower life expectancy and health status?  I doubt it does.

And I wish that the NBC, and all the other media covering running events here in the US and the rest of the world, would acknowledge that instead of focusing on the small risk of injury or death, there is a far bigger positive outcome to being active.  Maybe in future, doctors like George Chiampas will be explaining why those sitting on their couches SHOULD be getting up to run, rather than telling those who are running how not to hurt themselves doing it!

Fitness does not protect you, but nor does being under-trained increase your risk

One final point I have to make, in response to what I've seen is being discussed about this issue, is that people are not necessarily more likely to die from a cardiac event during exercise if they are untrained.  A lot of people have said that people who die during marathons are themselves responsible, because they're running when they are not fit enough.  This is not true, to the best of my knowledge.

The reality is that people who die during exercise have some underlying, probably undetected condition that predisposes them to a cardiac event during exercise.  Those who are simply unfit don't die - they just stop at the 10 mile mark (or sooner) and walk the rest of the way, because their brain does not allow them to continue running.  The fact of the matter is that there are conditions that predispose us to sudden cardiac death, and exercise can bring this out - but it could happen to the elite (Ryan Shay, a few soccer players in recent years) or to the average runner.  It's not that they're unfit or undertrained.

Of course, behaviours contribute to some deaths - overdrinking, for example, can lead to hyponatremia and death.  But even here, the criticism belongs with those who advocate excessive drinking, the dangers of "dehydration" and advertise sports drinks to unknowing consumers, not to the athlete who makes the mistake.

So in the light of the latest events, and until toxicology reports are in, deciding on the cause is premature.  Agreeing that it's sad for all involved, but recognizing that it's not running that killed them, is the way to go!


Friday, October 16, 2009

Ross speaks: Fatigue and the brain

Anticipatory regulation of exercise

Apologies for the delay in posting after my lecture last week at UIC - the Chicago Marathon came and went, and since then, travels have taken too much time to post properly.

However, what I've done below is post segments of that talk, which was titled "Limits to exercise performance: World records, fatigue and unphysiological performances".  Unfortunately, Jonathan was a little off at an angle, but hopefully the video is clear enough and the sound good enough to make out the argument.  Just in case, the diagram is shown below the video, so you can follow it there (hopefully).  Also, if you're getting this as an email, the YouTube clips might not play, so you may have to click here to go to the site and view the clip there.

The first video, 3:56 long, presents a model which I wrote about in an article published earlier this year in the British Journal of Sports Medicine, called "The anticipatory regulation of performance: the physiological basis for pacing strategies and the development of a perception-based model for exercise performance" (BJSM, 2009 Jun;43(6):392-400)

The model explained:  Complex anticipation and RPE

Obviously, you're watching a part of a presentation slightly out of context, but hopefully it gives you the basic idea.   This is a topic that has been covered a few times on the site - in fact, there's a whole series on Fatigue for those who are interested.

To summarize, your ability to regulate pace (which is something I'll bet you've never even think about) is vastly more complex than you may realize.  Even the most basic decision of how fast to start a 5km versus a 10km race is the result of innumerable calculations, which take into account previous experience, training, motivation, environment (internal and external) and physiological changes during exercise.

It really is a remarkable system, and one which we believe is primarily regulated by the perception of effort.  This is something you probably also haven't thought about much, but the way you perceive exercise is in fact so enormously complex that science is many years away from understanding it.

There is debate in science about whether your perception and the regulation of the pace is done consciously or sub-consciously, and that's where the debate seems "stuck" (or centered) right now.  I suspect that, as with most things, it will turn out to be a combination, for conscious regulation is obvious (you choose to slow down), but so is unconscious regulation - you don't have to think about starting pace, and you also slow down 'involuntarily' during exercise, even though your perception of effort is not necessarily raised (very important point this).

To explain, the physiological inputs before and during exercise result in a conscious perception of effort, which is then interpreted based on the expected duration and the "template RPE", which is a construct representing what would be considered an acceptable rise in RPE.  This interpretation of RPE underscores why exercise intensity changes dynamically during exercise.  It explains how motivation impacts on performance, and it accounts for the effects of changing conditions on performance.  This is why you speed up at the end of a race, even though your body temperature may be close to limiting, whereas you slow down in the middle, when you are not hot.

The idea that your physiology 'controls' pacing is flawed, because it ignores the importance of context - not all physiological inputs are interpreted equally!

Applying the model to the heat

The next video, shown below (2:30 long), shows a simplified model for what would happen during exercise in the heat.

We know that if your body temperature hits 40 degrees (maybe a little higher in highly motivated elite athletes), your ability to exercise is limited - this temperature is associated with nervous system failure, lack of co-ordination, dizziness, and a failure to activate muscle.

Put simply, if you hit an internal temperature of 40 degrees, your race is basically over - you either walk to the finish line, or you fall over in a cool spot and hope to cool off!

But luckily the body is too smart for this - the pacing strategy is adjusted in advance of this failure.  The previous video, on the RPE and the model for regulation, explains how this would happen.  What this second video is showing is that the 'calculation' is made in order to balance the requirements for fastest possible time with physiological 'safety'.

Obviously, stopping at the 36km of a marathon is failure.  So too is death from heatstroke.  But, equally bad is running twenty minutes slower than you could have done, because your brain has been "too conservative".  So the balance is achieved by forecasting the physiological outcome of current behaviour.  Put simply: "If I continue at this pace, storing this heat, will I finish the race before I run into danger?"

On a hot day, when heat storage is higher thanks to reduced heat loss, the answer may well be "NO", in which case the brain reduces muscle activation and thus pace, and the race can be completed in a slower, but feasible time.  The endspurt at the end comes when the body temperature is at its highest, but the risk is now absent, because the brain takes into account the exercise duration remaining, as explained previously.

So that is it in a nutshell - it's not all dreamed out of thin air, mind you!  The BJSM paper I linked to above contains all the references and evidence on which this model was built, so feel free to check that out!

Travel update

Just a quick travel update, seeing as how I'm making my way across the nation meeting all kinds of interesting sports science-related people:  I'm now in the Rocky Mountains, at an altitude of 3,500m, where I am learning new respect for Kenyan and Ethiopian runners who train at this altitude all the time!  I run at least a full minute per kilometer slower than normal, but my lungs feel as though they've completed 10 consecutive 800m races.

I head to Boulder tomorrow, where I will meet with a number of coaches, athletes and experts, and I'll be sure to interview and post interesting comments here.  So join us then!


Sunday, October 11, 2009

Chicago 2009 In-race splits

Splits from the 2009 Chicago Marathon

Below is a table with the kilometer splits (those we got) from today's Chicago marathon, which saw Sammy Wanjiru win his fourth major marathon - Fukuoka, Beijing, London and now Chicago.

His time? 2:05:41, one second inside the course record, so mission accomplished, at least from that point of view. The world record eluded him, but the cold, the wind and the pace-making (too fast early, didn't last long enough) didn't allow that.

The splits make for interesting reading. The early pace was unbelievably fast - 5km was reached in 14:34 and 10km was covered in 29:10, projecting a finish time under 2:03. It was hardly surprising that the pace slowed, and the second half of the race would be covered in 63:40, compared to the first half of 62:01. Abderrahim Goumri was sensible and probably ran the closest to an even split - 62:50 and 63:14.

Wanjiru's decisive move came just before 35km, when he shifted to drop the Kenyans who had kept pace up to that point.

The wind certainly played a role - it was coming from the North, and if you look at the table below, you'll see some really slow final kilometers - that's partly due to the race situation, the fast early pace, but also the wind, because the final stretch of the race is run directly into that wind.

Enjoy the splits below!

Thanks for following the coverage!

Ross & Jonathan



Elapsed time

Mile pace

Projected time







37F / 47%




































38F / 43%

















no time











37F / 44%












No time







No time

















No time


No time
















38F / 46%


























38F / 45%


No time






























38F / 43%












No time



final 1.195k



Note: The race doesn't do 1km splits, and so we're reliant on our own 'spotters' out on the course to report to us as the elites hit each kilometer mark, which we then match up against our official race timing. So we apologize for any missed splits, but here's our best efforts to track the race as it unfolds!

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