The “2-hour marathon” season begins


Below is a padded-out, expanded version of an article I wrote for The Times, an SA newspaper (I wrote a weekly column for them, every Monday)!

It deals with the two-hour marathon.  I do apologize if some of the concepts are familiar to you based on my previous writing, but obviously the target audience for the Times is a little different, so I took the opportunity of Bekele running in Dubai this week to talk 2-hour marathon concepts, and I’ve added a little to that for this post.

Bekele goes in Dubai on Friday, amid different reports of his desire to attack the World Record.  Some say it’s a training run for London, others say it’s a legitimate attempt.  My own “sources” say he is in brilliant shape and will go for the World Record.

I’ll cover it more later in the week!

Ross

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The Sub-2 hour marathon

At the start of 1953, the “race” to break the four-minute mile barrier was reaching its peak.  The World Record had stood at 4:01.4 since 1945, and so for eight years the prospect of 3:59 was there, imminent.

Also at the time, another physiological barrier loomed – Mount Everest.  So in addition to there being a race break the four-minute mile, there was a race to see which of these two ‘impossibilities’ would be achieved first.

It would be Hillary and Norgay, representing “Team Everest” who won that race, summiting on May 29, 1953.  Just under a year would pass before “Team Four-minute mile” crossed the line, thanks to Roger Bannister on May 6, 1954.  It remains the the most significant athletic barrier ever broken.

Why this history lesson today?  Because in 2017, we are entering peak fervour in the race to break another significant athletic barrier – that of the two-hour marathon.

The physiologist in me emphasizes a word of caution here – it’s only “peak” because marketing tells us so.  In reality, a true sub-2 hour marathon is a lot further away than some would have you believe.  The World Record currently stands at 2:02:57, by Kenya’s Dennis Kimetto, and at that level, take my word for it, 2:58 is an enormous amount to cleave off.  The last 2:58 took 18 years!

Another comparison is that the race for the 4-min mile was a pursuit to cut about 0.8% off the existing WR.  The sub-2 marathon is looking for 2.4%.  That’s a huge chunk to take off in a short time.  And those arguing for it have pointed me to Usain Bolt’s exploits in the 100m between 2008 and 2009.  Two points on that – first, that was a 1.6% reduction.  Since then, nothing.  And note also that nobody else is getting down there either.  We’re back in 2008.

Second, remember that we are already in a period of dramatic reduction in the marathon world record.  That’s why all this excitement started in the first place!  We were five minutes away within one generation of the current group, and now it’s three.  I feel that asking for a further 2.4%, on top of the 2% already achieved in the previous generation, would be unprecedented, and impossible without changing the context of the physiology.

Nevertheless, the barrier is now “in sight”, even if a telescope is required.  Hype began in 2014, when a group of sports scientists launched a Sub-2 project, saying that “applying a dedicated scientific approach” including, among other things, “intelligent training” methods could help it fall by 2019.

I found the premise objectionable, mostly because I hate when sports science writes cheques it can’t cash.  Over-promising helps nobody, and the idea of science as this knight on a white horse to help Kenyans and Ethiopians run faster with “science” and intelligence” also seemed a little arrogant to me.  It would seem that instead of offering help, the better approach might have been to ask for advice, seek to learn from the east Africans, and maybe help a European run under 2:06! ;-)

Then, last month, Nike announced their “Breaking Two” plan to take it on this year.  Why wait for 2019? Or 2035?

Three athletes, including Kenya’s Eliud Kipchoge, the best in the world right now, will run in a specially arranged race sometime between now and June (there’s good reason to think May is the month, again).

Is it possible?  The likelihood depends how far you’re willing to allow ‘rules’ to bend.  Without going into huge physiological detail, elite marathoners are constrained by three factors.  First is the size of their “engine”, which a physiologist talks of as maximal oxygen consumption – how much oxygen can they move through their lungs, heart and into their muscles?

Second, their efficiency – how “frugally” they’re able to use that oxygen.  We call this economy, and it’s no different, conceptually, to how you measure that your car gets 100km for every 6.2 litres of petrol, except we measure it in liters of oxygen.  The lower the better.

Third is the ability of that runner to sustain a high percentage of maximum for a long period.  This is the key one, because if that runner pushes a little harder, getting closer to maximum, then all kinds of physiological changes happen that would force them to slow down.   This is where the physiology gets a little more complex, and where you need to move beyond an over-simplistic model of “oxygen supply limits performance”, which is unfortunately what this 3-corner “constraint” theory can lapse into.

The reason we talk about these three factors – maximum capacity, economy and sustainable intensity – is because they’re good gauges for the physiological demand of the system, but that’s not meant to imply that they’re the DIRECT limit of performance.  For instance, if a runner increases their speed, they push the intensity slightly higher, and yes, they’re closer to their maximum oxygen carrying capacity, but there are also dozens of other physiological consequences.

One is that their rate of heat production rises, and if that cannot be offset by heat loss, then body temperature rises and we know that this may be limiting under certain conditions.  Another potential outcome is an increased rate of glycogen use, and that can lead to fatigue at the level of energy supply to the active muscle.  Loading on muscles and tendons, as well as the accumulation of metabolites all factor in if the athlete pushes too close to that limit (which we measure as VO2, mainly for convenience).

My point is, the model for marathon running is a triangle with three corners – max O2, O2 economy and % of max O2, but in reality, they’re just measurable components of a far more complex system.

Conceptually, they’re still valuable, however, and the third of them in particular is crucial because there is without doubt a ‘barrier’ in terms of how close to maximum the athlete can run before physiology starts to ask for ‘payments’.  Elite athlete physiology is a magnificently finely tuned system, and that’s why the 2:58 reduction won’t happen at the click of a finger.

If the 2-hour marathon is to fall, it would take a large improvement in one, two or all three of these ‘constraints’, and that requires more than just evolution.  It calls for revolution.

Nike may well succeed, but they’d need to change the entire context of running physiology.  One way would be to run it downhill, as I explained previously

Then there’s always doping.  I was especially startled to see Sarah Barker’s recent interview with Jos Hermens, linked to the Sub-2 project, in which he spoke of genetic testing to identify the best young athletes, followed by the not trivial suggestion that they might “manipulate those genes, “turning up” those that would benefit a long distance runner and “turning down” those responsible for performance limiting factors like lactate production”.

There’s a bit of science fiction in that, and Hermens is not a scientist, so I’ll give the benefit of the doubt there.  Also, there’s no indication that anyone is actually doing that, and I’ve no specific, direct reason to suggest anything nefarious, other than the known issues around east African non-existent testing.  But that’s a startling direction to be facing.  “Purists will say this is doping,” Hermens said, “but what about altitude tents? It’s a similar thing.”  Slippery slope stuff there.

Sport over the last two decades has been  nothing if not consistently able to show us that when the incentives are great enough (and sometimes not even then), people do go to extreme lengths to succeed.  The “experiment” to break 2 hours invites all manner of those extreme lengths, and that does make me nervous.  Not necessarily now, but if momentum builds.  I’ve yet to see a clear and transparent plan from Nike, for instance, on how they’ll ensure that EPO doesn’t power the preparations for their Breaking 2 project.

If you start the physiological equivalent of an “arms race”, then people will eventually find the heavy weaponry.  It’s human nature.

Anyway, back to reality.  And naivety:

There’s reason to think that the likeliest tactic this year will be a shoe that changes the relationship between those three factors I mentioned earlier.  A shoe with springs, for instance, would allow a runner to go the same speed using less energy.  Ergo, they could go faster before a potential limit is reached.

Indeed, I suspect this shoe already exists, has been used by a few runners in the last year (Rupp, Bekele), and will be used by another great marathon runner, Kenenisa Bekele, in a marathon in Dubai this coming Friday, so keep an eye out for a potential world record there, and a hint of what may be to come.

For Bekele, if the conditions are cool enough, and the wind does not pick up, then the record is certainly on.  They’re starting the race earlier than previous years in the hopes that those two factors can be avoided.

Then what becomes crucial is the ability of pace-setters to stay in it for as long as possible.  It is no co-incidence that the last World Record, as well as the two ‘scares’ in 2016, were set in what were basically races over the final 10km.  Bekele benefitted enormously from Kipsang’s aggression between 25km and 40km in Berlin last year.  In the absence of such a race, he’d need structured pacers to stay on until 35km, or he’d need to attack the final 12km solo.  Tough ask, but possible.

If it does happen, it’ll be funny to watch the various groups clamouring for credit.  The Sub-2 project spoke of their involvement with Bekele after Berlin, and if he does run in the Nike shoe (whether they’ll say anything, or even whether the shoe is ‘innovative’, I don’t know – I am speculating there, hope you appreciate that), then they may too.

I’ll post more on it in the coming days, no doubt.

Ross

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