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