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Sunday, September 30, 2012

Geoffrey Mutai: 2:04:15, misses WR

Geoffrey Mutai runs 2:04:15 - an intriguing, but ultimately unsuccessful WR attempt

An intriguing, but ultimately unsuccessful world record attempt has seen Geoffrey Mutai win the 2012 Berlin Marathon in 2:04:15.  In one of the more amazing (or peculiar) finishes in a marathon, Mutai and Dennis Kimetto passed through the Brandenburg Gate locked together, but a sprint never came.  Either both were too shattered from chasing the world record, or they'd agreed on a finishing order (they are training partners, Mutai the senior man), but the final 2.2km were incredibly slow relative to what went before and the record, which seemed on at 35km, fell away and was ultimately missed by a fairy large margin.

In the aftermath of the race, there's been a good deal of discussion about the finish.  As mentioned, Mutai and Kimetto hit the Brandenburg Gate locked together, Mutai slightly ahead, as they had been for pretty much 42km.  Over the final 200m, that did not change, and there seemed to be no attempt to change that from Kimetto, and no attempt from Mutai to seal the win with any kind of sprint.  A few commentators have remarked at their surprise at the lack of a sprint, and I must confess it was an anti-climactic finish for a head-to-head race, leading me to side with those saying it was "pre-planned".

If that is the case, it would continue a theme started in the London Olympic Games where athletes were getting into trouble as much for NOT wanting to win as for cheating in order to win.  We often talk about doping undermining our chance to watch a "genuine race", and one can argue that this is the same, and a shame for the integrity of the concept of a 'race'.  Then again, these athletes are professionals, and given the "hierarchy" that would see Mutai above Kimetto as training partners, perhaps they are entitled to 'share the pie' as they see fit.  Feel free to voice your thoughts in the discussion below.  Here are some thoughts from our friends at Letsrun.com

Patrick Makau's world record therefore survived it's first really big challenge, and it illustrates once again just how challenging the world record is, because Mutai had it in his sights, and perhaps hindsight will show that a small error in pacing after 30km, when he surged aggressively for a 14:18 five-kilometer split, cost him over the final 5km, where the pace dropped significantly.

The race analysis

The story is best told by the graph below, which is full of detail, but hopefully tells of how Mutai controlled the race from the start, and managed to wind the pace up progressively so that each five kilometer segment was faster than the one before.  Until the final 5km segment, that is, where you can see the "cost" of the surge as the pace dropped.

Up to that point, it was a remarkable illustration of negative pacing, and is the kind of thing you might occasionally see in a tactical track race, let alone a world record lasting over two hours.

Briefly, the graph compares Mutai's 2012 race to that of Patrick Makau, the man who set the record one year ago.  It shows, from top to bottom:

  • The five kilometer segments for both athletes, with Makau's in red and Mutai's in blue
  • The difference between the five-kilometer splits in purple.  Positive means Mutai was slower, negative means he was faster than Makau for the comparable split from 2011
  • Projected marathon time for Mutai in the white blocks
  • The blue line and red line show the race splits for Mutai and Makau respectively.  The text on the graphs shows the cumulative time difference between the two men as Mutai's race unfolded

So, what are the key points?
  • Firstly, the AVERAGE pace needed to run the world record is 2:55.8.  That translates to a 14:39/5km.  Notice how Mutai did not hit that pace until the second half of the race.  In fact, he was actually quite a lot slower than the overall average, with his splits for the first 10km projecting a time outside 2:05.  So the first half was conservative - 62:12.

    Interestingly, I've since received some feedback that the pace car that drives the route with the elite athletes displaying the kilometer splits was responsible for this conservative start, because it "froze" with a kilometer time of 2:50 within the first few kilometers of the race.  Mutai, assuming he was basing his pace on that information, would have consciously held back for fear of maintaining that kind of pace, and the consequence of that is that he went through the half about 35 seconds slower than had been requested.

    Once Mutai realized that the pace was too slow (he needed a 61:25 second half), he pressed on, and the second began in a sensationally aggressive fashion, and was fast, at least until the end.  His second half ended up being 62:05, so on paper, an even race, but of course it's skewed by the very fast surge and the very slow finish

  • Speaking of the finish, at 35km, the world record was definitely on.  Makau's comparable time may have been 14 seconds faster, but Makau finished fairly slowly last year too - 14:59 for the last 5km.  Had Mutai maintained even a 14:40 pace from 35km onwards, the record was his.  However, he slowed significantly.  The final 2.2km were run at 3:09/km.  The result was that a virtual gap of 8 seconds at 40km became 36 seconds by the finish line.  Mutai was absolutely spent over the final 2.2km, and this is probably the outcome of the 14:18 surge.

  • Until the final 7km, the slope of that line is just incredible - yes, the start was conservative, but it was ramped up as the race developed, culminating with Mutai's big surge between 30 and 35km, when the pace-setters dropped out.  There, a 2:43 and a 2:52 kilometer put him right back in the frame for that record.  It's easy to see in hindsight, but that was too fast - a slightly more conservative pace would still have kept that line heading in the right direction, and Mutai MAY have had more in the tank from 35 to 40km, and certainly a sub-2:04 would have been achieved.  These things are never precise, of course, but given how beautifully controlled the pace was, that surge was just too big.  And to emphasize the precision, we're talking 2 to 3 seconds per kilometer here!  Those are the margins.

  • Look at the cumulative time gaps between Mutai and Makau - the conservative start for Mutai meant that from the gun, Makau was "ahead" in their virtual race.  It was 22 seconds after 5km, and the gap got larger and larger, so that by 20km, Makau would have been about 200m ahead, with a margin of 33 seconds.  But Mutai's race, as mentioned above, was based on getting quicker and quicker, and so he began to erode that margin.  21 seconds at 25km, then it got larger again - that's because Makau used the 25-30km segment last year to surge and break Gebsrselassie's challenge.  The virtual gap grew to 34 seconds at 30km, but Mutai had his own surge still to use.  That happened from 30km to 35km, and suddenly, the record was back on because the difference was now down to only 14 seconds.  With 2.2km to go, Mutai had Makau in "his virtual sights".  But then, as pointed out above, Mutai blew and the record fell away.
Ultimately, Mutai's performance today showed just how difficult it will be to get this record.  There is still a margin for "error" in terms of pacing, but it's now tiny.  Today, the start was probably a touch slow, but the big difference came after 35km, when the pace told.   Similarly, for Makau last year, his big surge probably meant that the final time was not quite optimal - there is a margin for error.  But in the heat of a marathon, it's small enough that surges and decisions that are slightly fast are costly.  This is why it's so premature to talk about a sub-2 hour marathon, or even a sub-2:02.  Those performances require perfection - the small margin of error for a 2:03 is almost non-existent for a 2:02.  Weather-wise, it has to be perfect (the sunshine may have added time to Mutai's performance today, for example, just slightly warm by the finish), pace-setting must be perfect, the athlete probably requires some 'company', and of course their condition must be absolutely perfect on the day.

Mutai, and Berlin, were not quite 100% today.  The result is a PB (official course, that is - Mutai has that 2:03:02), and Mutai has now won three major marathons (Boston, New York and Berlin), but the world record waits for another day.


P.S.  Will try to get thoughts on the women's race up later.  I missed the race live because of another commitment (sorry for the lack of live splits - work got in the way!), so have been scrambling to get this short analysis done.  More later, work permitting!

Saturday, September 08, 2012

Pistorius vs Oliveira and technology. 3 quick thoughts on Round 4

Pistorius vs Oliveira and Technology.  Three quick thoughts on Round 4

Tonight sees the final evening of Paralympic action and it will be highlighted by the fourth clash between Oscar Pistorius and Alan Oliveira.  Oliveira stunned the world when he beat Pistorius in the 200m final last weekend, igniting a debate about the length of his carbon fiber blades.

Ironically, it was Pistorius who supplied the kerosene and the match to start the 'technology bonfire', which has not relented.  Pistorius has, for the last five years, defended his prosthetics and claimed that the technology does not provide any relative advantage.  A first defeat over 200m in nine years, and his first interview called out the technology used by a rival, and that has enormous implications for how we perceive the carbon fiber prosthetic technology in the sport for ALL its users.

Pistorius was both wrong and misguided in his explanations and reasoning for his protest.  Wrong, because he claimed that he couldn't compete with Alan's strides, when in fact, it was Alan's stride rate that was the difference (Pistorius had longer strides, by about 8%, it turns out).  If he loses the 400m final tonight, it will be for the same reason, so look for the stride rate differences.  Misguided, because the IPC have a set of rules or formulas in place that govern the length of athlete's blades and Oliveira was comfortably beneath these.  The IPC guidelines allow Oliveira to run up to 1.854m, and he competed at 1.81m.  For Pistorius, incidentally, the IPC allows 1.93m and he races at 1.84m.  More on this later.

In the larger scheme of things, however, what Pistorius did achieve was to draw attention to the fact that rule changes may be needed, and I think the implications of that were lost on him somewhat.  I explained more of this in my post at the time.  I'm not sure what rule change they can make, without discriminating against one athlete but not another.  Ironically enough, Pistorius' CAS appeal was against rules that he felt discriminated against one athlete, and now he's effectively asking for a rule change that would in all likelihood allow him to benefit at other's expense.

Every double amputee, at some stage, has the opportunity to "optimize" the technology and specifications of their carbon fiber blades.  For Pistorius, this came in 2007/2008, when he was flying to Iceland to try prototypes with Ossur, and doing all kinds of testing before taking his case to CAS for the right to compete against able-bodied athletes.  Back then, he competed at a height 184 cm when the IPC rules would allow 193 cm, and he now is obliged to stay at that height after the CAS decision.  What we should be asking is why he was at this shorter height in the first place?  He had 9 cm to play with back then, but all the testing and engineering support from Ossur saw him embark on his campaign at 184 cm.  For Oliveira, no such CAS-ruling exists, though it might in the future, but he is the sport's next uncomfortable problem.

The scientific evidence suggests that length is one of a few reasons why the blades may provide a relative advantage.  Oliveira's emergence on the 'blade runner' scene means that we now have two athletes with access to the technology and the skill to use it, and suddenly we don't know which is the better athlete, because the technology confounds it.   Read that previous sentence once more, except replace "Oliveira" with "Pistorius" and you see the problem with the cross-over of amputees into able-bodied events.

Looking ahead to the 400m final. Quick thoughts

In any event, let's leave the big picture behind and look ahead to tonight's clash in the 400m final.

Before their 100m final (Pistorius was 4th and Oliveira 7th), the cameras focused in on the prosthetic limbs of each athlete, further showing that for all the exploits of the athletes in London 2012, the 'stars' of this particular show have become the devices they run on.

In their 400m semi-finals, both shut it down with about 100m to run, so their qualifying times don't tell the true picture.  I think the better "preview" for the race is that they went through 200m in identical times, around 23 seconds, and so except them to be level with 100m to run tonight.  It's sure to be a great race, determined largely by whether Oliveira, just 20, has the strength over the distance compared to Pistorius.

Or will it?  Perhaps the technology will have the greater impact.  Here are three things to keep in mind when this debate kicks off again, as it inevitably will.

1.  Don't look purely at the length of the prosthetic limbs

Much has been made of the fact that Oliveira runs on blades that are 47cm long, while Pistorius' are 41cm long.  Failing to think this through, people claim "Ah, that's proof, the Brazilian has an advantage".  The commentator on the world feed, who is absolutely dreadful for many reasons, the least of which is ignorance, points this out all the time.

The truth is more complex.  Imagine for a moment two men, both double amputees, identical in every respect, except for WHERE their amputation is.  One is amputated just above the ankle, the other just below the knee.  That means a ± 15 cm difference in their height WITHOUT prosthetic limbs.

If you now provided blades that are the SAME length to both these men, you'd be putting one on stilts (the above-ankle amputee), the other on 'stubs' (the above knee).  The higher up the amputation, the longer the blade has to be to create "equality".  This is why, when you compare Pistorius to Oliveira, you cannot simply look at the carbon fiber blades.  Pistorius' amputation is low down, whereas Oliveira's is higher up - you can see this in all photos, just by observing the socket that the carbon fiber blade is attached to.

Now consider two differently sized men.  Here, you have an even more complex situation, because even if the amputation is in the same place, they may require different blades, because one of them is Usain Bolt (tall with long limbs), the other is Tyson Gay, shorter.

The point is, you cannot standardize the length of the blades because a) you have to allow for where amputation is, and b) you'd be disadvantaging taller runners with relatively shorter blades, and vice-versa.

So when the camera zooms in on Pistorius and Oliveira either before after this final, don't just look at the blades, because it's only a small piece of the story.

2.  There are not two different sets of rules for Pistorius and the others

In the aftermath of Pistorius' defeat and protest, a number of people claimed that Pistorius had a point because there are two different sets of rules, that the IPC has one set of guidelines whereas Pistorius is bound by the IAAF to run on his "shorter" blades at a height of 1.84m.

This is untrue.  Firstly, in IPC-sanctioned events, Pistorius can go up to 1.93m.  This was quite clear after the IPC leaked a document that shows the maximum allowable heights for all the double amputees.  That is shown below.

So, Pistorius could, if he wished, lengthen his blades for IPC races, just not IOC or IAAF events.  Granted, that may be very difficult to do, making the change from shorter to taller, so you can appreciate that he wouldn't do it.  Then again, Oliveira managed, within a few weeks, to get faster on slightly longer blades, so it's not inconceivable.

Secondly, however, we have to go back to 2008 again - the IAAF did not have guidelines in place for the length of blades, because there was no precedent.  So, at the time when Pistorius gave them this question, they borrowed the IPC formulas.  The result is that the IAAF would have the same formula and height restrictions as the IPC, and which you can see above.

The exception (for IAAF events only) is Pistorius, because of the CAS-ruling that "locks" him in at 1.84m, as I explained previously.  So it's not a question of different rules, but rather that the scrutiny has provided a selection of sorts that means Pistorius cannot now add length.

However, even this is not the most important point to recognize.  That is, I think there are more pertinent questions that need to be asked.  For example:
  • Oliveira has admitted that a few weeks ago, he increased the length of his blades, taking his racing height from 1.77m to 1.81m.  That has made a significant difference on his performance.  The question is, having gone up 4cm, why not go up another 4cm to his limit?  If height was the be-all and end-all decisive factor, he'd have gone as long as he could within the rules.
  • Similarly, Blake Leeper and David Behre are not competing at their maximum allowable heights either
  • Third, and very importantly, going back to 2008, Pistorius had 1.93m as his limit, but was already at 1.84m.  As a result, he's now obliged to race at that height by virtue of the CAS-ruling that prevents him from deviating from what was tested and approved.  However, we should be going further back, as I said above, and asking why he was competing so "short" in the first place?  All the investment by Ossur into Pistorius' campaign, and they "left out" 9cm?  More likely, they tried and found that 1.84m was the optimal length
I don't know the answer to these questions with certainty, but I can hazard an opinion, and it's that adding height does not mean a faster overall performance.  It may mean a higher top speed and better finish, but there is a compromise in terms of the effect of longer blades on the start and the bend.  Watch Oliveira's 100m race to see this.  Part of it is that his amputation is higher up, and part is due to 6cm of additional blade length.  Blake Leeper has the same issue because he is also amputated higher up.  My point is that the athletes settle on a racing height that is lower than the allowable limit for a reason - best performance.  Claiming that height is the crucial factor is to overlook all the other factors that affect performance.

What we are seeing in the Paralympic double amputee events is a race where athletes have tested their equipment, found the optimal specifications for OVERALL time, factoring in how much is lost at the start and gained on the straight, and now compete against one another.  And that's great, it should be celebrated and enjoyed for what it is.  Oliveira, for whatever reason, may be better able to manage or control longer blades, still within the IPC limits.  Perhaps in the future, another athlete will be even better.

Just a quick word on those limits shown above.  They are based on measurements of other limb segments in able-bodied athletes, and then used to calculate what the person's maximum height can be before they become "disproportionately long-legged".  That number - the 1.93 or 1.854m - is not the average, however, because you will find that some people have longer legs relative to arms.  So the IPC must work with a range, perhaps average ± 2SD.  Then they add 3.5% to allow for athletes running on their toes.  Interestingly enough, if they took this 3.5% off, Pistorius' limit would drop to 186.4 cm and Oliveira would drop to 179.1 cm.  Presumably, this is what Pistorius considers fair and would accept as a rule change.

3.  Oliveira has allowed us to see the effect of technology

Final point - the only reason this debate is happening is because Oliveira has so publicly allowed us to see how the technology affects performance.  Here is an athlete who is clearly good - even if he is forced back to 179 cm with the removal of the 3.5% rule, for example, he'd be right up there in a Paralympic final, and this at the age of 20.  However, he's gone from good to great as a result of a technological improvement.

I'd argue that there is nothing wrong with this.  You could, playing devil's advocate, argue that Oliveira was running too short in the first place, back when he was at 1.77m, and now he's gone up to where he should be.  Or, continuing along the same lines, you could say that his unique skill is his ability to use those blades better than others, allowing him to use longer blades.

However, the difference between Oliveira and the others is not that he can do this "Formula-1 like" engineering of performance - they all can.  Rather, it's that he did it at a time and in a place where it is so clear for all to see.  It was the visible change that brought it to our attention. Reps for the companies that make the blades regularly help athletes with performance testing, trying out new blades, new materials, lighter mass, thinner blades, different ways to attach the blade to the stump, and of course, length.  They do this in the off-season, and the effects are not as obvious as they were for Oliveira, but they are there.

It's part of the sport, and so within guidelines set up by the IPC, it should not even be questioned provided it happens in Paralympic events only.  If anything, it should be encouraged and celebrated as a symptom of an advancing, improving sport.  In that regard, it's no different to cycling enforcing rules about bicycle specifications, or Formula-1 rules regarding car design, but still driving innovation in the search for a competitive advantage.  We can question those guidelines, but that's only because one person (and the obliging national federation in SASCOC) feels they unfairly prevent him from winning.  

And it is only 2012.  By 2016, there may well be four or five MORE double-amputees, inspired by Pistorius and Oliveira, who are even faster.  In fact, it is not inconceivable that the winning time in the men's 400m T44 final will be faster than the able-bodied winning time by 2016.  It all depends on the technology ruling.

History will judge the athletic ability of both Oliveira and Pistorius, because in future, with the continued growth of the Paralympic movement, times will drop, possibly significantly if the caliber of athletes can increase.  So far, the assumption for both is that they are genuine 21s or 46s 400m athletes.  If that's true, no problem.  If it is not, then some time in the future, a genuine 45s 400m runner will have the same technology and skill to use it, and then it will become obvious.  Time will tell.

Until then, we watch these races wondering if we're seeing the best runner, the most skillful practitioner, the best engineer or the wealthiest athlete win.  And yes, that's sport (think sailing, cycling), but it's never been a dominant characteristic of running.  The whole debate brings attention to the cross-over from paralympic to able-bodied events, and highlights just how complex it makes the sport.  Celebrate them for their differences, but recognize that they're different.


Monday, September 03, 2012

Oscar Pistorius: Counting strides (as requested) and more thoughts

Oscar Pistorius beaten, and then invites debate on someone else's technology

Talk about irony.  Within minutes of being upset by Brazil's Alan Oliveira in the final of the men's T44 200m, Oscar Pistorius claimed in this interview that he's "not running a fair race here".  The crux of his argument, which he also stated yesterday before even losing this final, is that his rivals are artificially extending the length of their legs, and he pointed out in this interview that "it's very clear that the guys have got very long strides".

To add to that case, he is quoted after the final as saying the following: "I can't compete with Alan's stride length".

Now, let me start upfront by saying that there is a lot more to running that stride length.  If all it took was big strides, then the running world would be dominated by the tallest men, and shorter runners like Tyson Gay would stand no chance.  What matters is not just stride length, or height, but rather the length of the leg relative to height, and the ground contact length, which is a function of the leg length (partly).  Plus there is force applied to the ground, leg turnover rates and all those things, but let's take one component at a time here!

Read more. . .