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The year is rapidly winding down with Christmas approaching, and with the festivities planned for next week, today may well be the last day that many of our regular readers are in their offices. If you're anything like me, you're only there in body, your mind is already looking ahead to the holiday break, however long or short it might be!
But before a lot of you left and stopped reading for a while (we hope it's only a while!) we thought we'd take this opportunity to thank all of our regulars, our subscribers, our visitors and especially the people who've contributed to making "The Science of Sport" so stimulating for US to write through their great comments.
We are extremely flattered whenever anyone is positive about the work and thanks us for the articles, but you should know that it's as stimulating and interesting for us to bring sports sciences across in a more entertaining, news-relevant manner, so we should in fact be thanking you!
We're proud to have such a discerning and informed following - some of the comments we receive would not be out of place in a scientific discussion at a conference (actually, some of the scientists at those conferences might find themselves out of place discussing concepts with some of you!). I would list some names and give specific references, but I know I'll leave people out, so let's leave it at ALL of you!
A special nod of appreciation, incidentally, go to one zig600@yahoo.com - you couldn't have know this, but you were the first person to ever sign up to receive our daily posts via email (you can do this at the top left corner of the site, incidentally)! And then to the next 368 people who've done the same, (welcome (Annethea, you are the newest 'member'!), thank you for inviting us into your inboxes!
What does the remainder of 2007 hold in store?
Things slow down to a crawl over this part of the year, especially here in SA where it's our summer break - most people have been off for a week and probably only return to work in early January, so we're going to save our series for 2008 - altitude, lactate, fatigue, and whatever else is thrown up!
Until then, we will look back on the year that was, and give some of our more entertaining analyses of sports events from the year past. We'll also look ahead to 2008, a Nostradamus exercise of predicting the future as a bit of fun!
2008 being an Olympic Year, with all attention geared towards Beijing, there will be some fantastic news for us to write on, as well as some hopefully interesting series!
With that, then, we would like to wish all our readers a very safe, happy, and rewarding Christmas and New Year. If you are travelling, do so safely, keep training, and we hope 2008 is a prosperous year for all.
Best wishes
Ross
Jonathan
Kamis, 20 Desember 2007
Selasa, 18 Desember 2007
Oscar Pistorius banned - IAAF result
NEWS FLASH:
On January 14, the IAAF issued a report revealing the results of scientific testing done on Oscar Pistorius. If you would like to be redirected to a summary of those results, click on the links below:
- IAAF Announcement: Oscar Pistorius banned - IAAF report findings and analysis
- Oscar Pistorius to challenge ban - Insights and discussion on the results, the history of the debate and what the future may hold for the debate
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Leaked reports that Pistorius' Carbon fibre prosthetic limbs provide a "considerable advantage"
The IAAF tests on Paralympic athlete Oscar Pistorius have now been handed to IAAF President Lamine Diack, and the early reports are that the tests have indeed confirmed that the carbon fibre prosthetic limbs, knowns as "Cheetahs", do in fact provide Pistorius with "considerable advantage" over other runners.
Unfortunately and frustratingly for us, the IAAF have issued a press release which states that "the IAAF does not plan to discuss the contents of the report, or make any public announcement about any decision related to the report, until 10 January 2008". Because of this, we don't have access to the specific results and so we cannot, unfortunately, bring you any more detailed insights or interpretation of the specific test results. But the lead researcher, biomechanics expert Prof Gert-Pieter Bruggemann was quoted in a German newspaper as saying that the advantage is considerable - several percentage points in size. Apparently Prof Bruggemann was himself surprised at the size of the difference.To be quite honest, I'm also surprised at the apparently definitive result, but not because I don't think there is no advantage (I'm on record as suggesting about 5 seconds advantage, and only next year will the actual facts emerge), but rather because of my slight scepticism about the tests the IAAF eventually put him through. I think that the IAAF took on a brave, but essentially impossible question to answer by trying to find the mechanisms and underlying physiology for the potential advantage.
However, returning to the tests, the focus was clearly on the oxygen consumption and lactate accumulation during running. There was a very sound physiological basis for investigating oxygen consumption, but lactate was not quite as clear cut. There were also many potential pitfalls and possible problems with the measurement of these variables during a short duration sprint and sub-maximal exercise bout, so I'm not 100% convinced the issue is resolved - in my opinion, it has been for a while, but whether this result will end it, I'm not sure.
But because the test results are not available yet, it would pure speculation as to what they found. I suspect that his oxygen consumption must have been radically lower than other athletes', but I would suspect even more strongly that the biomechanical assessment of the limbs (apart from the physiological data measured when he ran) were the clinchers in this argument.
The theoretical basis for an advantage
Now, it may seem radical to some of you that the prosthetic limbs actually provide an advantage. This is a case that has been absolutely gripping as far as sports science goes, and earlier this year, when we did a series on Pistorius and the possibility that he had an advantage, we tried to explain just what the basis of that advantage would be, and it produced some excellent debate and discussion (mostly, anyway!)
I think that in our 8 months of existence here at The Science of Sport, the longest post we ever did was one I wrote looking at all the available evidence and theories for Pistorius having an advantage. This was an epic post to write (and probably even more challenging to read!) so rather than rehash all the same old points, and put you through that test of endurance, I refer you onto the following post if you are interested in some of the relevant arguments:
The main point we were making in this post was that because the carbon fibre limbs are providing elastic energy return without any possibility for fatigue, Pistorius would have a substantial advantage that would be seen most in the second half of his races. The human tendon is also able to provide energy return, but it comes at a cost - this "cost", while difficult to quantify, results in what we recognize as fatigue, with the athlete slowing down progressively as the race develops.
The Cheetahs, however, provide "free energy" the whole way around. In addition, the far lighter limbs (carbon fibre vs. bone, muscle, fat and blood = major weight difference) would also provide an advantage. There was a bit more to it than just this, but it's covered in the above post for interested visitors. But basically, the hypothesis created based on this theory is that when everyone else was slowing down (despite the fact that they're sprinting maximally), he would be speeding up.
With this hypothesis in mind, we waited for his first European race in Rome, and analysed his pacing strategy during that race. Sure enough, Oscar Pistorius ran a 400m race that no athlete has ever done - even the great Michael Johnsons and Jeremy Wariners were running a race completely different to Pistorius. We covered this analysis in the following post:
Now this finding alone could well have been enough to conclude that the advantage existed. In trying to find the mechanisms, the IAAF were really taking a chance, because mechanistic physiological studies are really very difficult to do. This one was particularly challenging, partly because of the fact that he is a sprinter (it's far more tricky to interpret VO2 data in sprinting than long distance running), but also because of the emotional aspect of the issue.
An impossible question to answer
In fact, this is one of the most challenging scientific questions that I can think of, and if we had an award for "Stimulating science question of the year", this would be it. The main issue is that the study is impossible to do "properly". In other words, you cannot have a Control group, because you can't have other athletes run on carbon fibre blades, and you cannot measure Pistorius running on normal limbs! So to actually ask the question "Do the blades give Pistorius an advantage over other runners RIGHT NOW?" is an impossible one to answer with 100% certainty.
And this is where many of the problems developed, because people, understandably, want this question answered. One has to realise that no one can answer this question, though.
Instead, the real issue was never whether this particular model of limb on this particular athlete provide an advantage. The real question that should have been asked is "Is Pistorius different from able-bodied athletes in a PREDICTABLE, measurable manner?" Because IF you can find difference, and IF you had predicted those differences based on the theory and physiology explaining them, then you would know that something was at play with the prosthetic limbs. And the extension of this difference, is that regardless of whether he's better now, technological developments in the future would further improve the limb and eventually, this measured difference will become significant enough to see the athlete win. Now, the pacing data from Pistorius' race in Rome was highly suggestive of this difference, and it was definitely a favourable difference.
The crucial point made in the earlier series was that if Pistorius went away and spent 2008 training and working with the engineers who make these blades, would he come back in 2009 running 2 seconds faster? If so, was it his hard training, or was it the technology? Ultimately, you'd never know, and for that reason, preventing the use of the carbon fibre blades was the correct way to go.
The IAAF - substantial investment and accommodation
The IAAF have been exceedingly gracious and accommodating in this case. They have bent over backwards, forwards, sideways, and done handstands in order to accommodate Pistorius on this issue, even paying for the tests to be done (a figure that would be in the high five figures, for the advanced type of testing that was done). Not that it is wasted funding, because the question was so fascinating and relevant, but because I don't believe it was ever the responsibility of the governing body of the sport to prove the presence of an advantage, especially given that they have rules in place to regulate the equipment used by athletes.
Instead, I really do believe that it should have been up to the Pistorius team to prove that they did not have an advantage. That is, they were the ones requesting permission in a special case, so would have been well-advised to prove that the limbs were not advantageous themselves. Of course, the IAAF probably would have done their own testing, but had Pistorius and his team approached the IAAF with some data, their position would have been enormously strengthened.
One of the most telling indictments on the situation is that in 2005, I was called up by members of the Pistorius team who were looking for an "endorsement" that the limbs did not provide an advantage. I would not give that endorsement in the absence of test results and proof, and neither could Prof Tim Noakes, who I know was contacted as well. Both Tim Noakes and I advised them to get the scientific testing done before they even contemplated the bid to compete in Beijing. We both invited them to come down to meet with us in Cape Town and discuss the way forward, because it was quite clear that the science was the key and had to be negotiated eventually. Yet two years passed and nothing was done.Now, the million dollar question - if it meant that much to you, and you were desperate to compete, and you KNEW that the scientific evidence was going to make or break your attempt, why would you not have had the testing done? So why not be proactive and make it even more difficult for the IAAF to prevent you from competing later on?
Instead, Pistorius and his team went on what the media called "PR and support generating tours" of the USA, drumming up support and funding for his effort - everything but the science. I was involved in a TV debate on the issue - the problem was that we never debated anything, because any science that was put forward was simply brushed aside and we were reminded that he is inspirational and a role-model. I agree on both points, but it definitely highlighted an aversion to proof, perhaps because that proof would should what that IAAF now have?
The focus on the support and PR was understandable though, I suspect most would do it, but it does highlight the difference in incentives between the groups. And ultimately, it was left to the IAAF to carry the can, and despite some debatable science tests, they carried the situation as well as I think anyone would ever expect.
What next for Pistorius?
As for Pistorius, there was a time earlier this year when the issue was topical and in the media every day, that he actually threatened at one point that if they banned him from running in the Olympics, he would quit the sport altogether and not even run at the Paralympics. This was an unfortunate comment, because he was effectively holding himself to ransom. Also, it didn't demonstrate much respect for the Paralympic movement, and for the enormous role he could play as a role-model for people everywhere. Make no mistake, Pistorius is an inspirational character - it's not for nothing that Tom Hanks has visions of a movie of his life! So I really do hope that he is able, assuming he accepts this decision, to move on and continue to inspire people with his determination and courage. The emotional issue should always be seen as distinct from the scientific one.
But for now, I feel the IAAF have made the right call - it's taken a long time, and it may not even be finished yet! But based on the theory and the limited results so far, it's a decision that is in the sport's best interests.
We'll do our best to bring you detailed reports and scientific interpretation as they come, if they come!
Ross
Minggu, 16 Desember 2007
The Mitchell Report at a glance
Fishing for guppies and landing a whopper
Former Senate majority leader George Mitchell's report on drug use in baseball was released on Friday afternoon, and sent the pundits and talking heads venting over the airwaves this past weekend. It is a behemoth of a report at 409 pages, and for all of those with some spare time this holiday season, you can download it here, while those with admittedly less time can view the executive summary here.
In the beginning many thought this was a fishing expedition of epic proportions, and was destined to return empty handed, or with only a few small time offenders. However in the end they landed a legend of baseball, the seven-time Cy Young winner Roger Clemens. Many other names were included in the report, and a history of drug use in baseball over the past 15 years is an important addition.
Also, on Sunday night Alex Rodriguez appeared in an interview on 60 Minutes, denying any drug use and also stating that he never once saw any illicit activity, although mentioning that there was always talk about it here and there.
Besides the players who were named in the report, the biggest loser is probably the Players Association. Mitchell states plainly that the association was "uncooperative" in many ways:
"The problem is serious"
Ok, so tell us something we do not know! As obvious as Mitchell's statement sounds, it is an important step in this process. Yes, the pundits and bloggers would all agree, and have all been saying for a long time, that indeed the problem is serious. However we lacked the hard evidence and inside information to back this up. Mitchell's report now goes on the official record and we hope this leads to future steps in the right direction for baseball (and perhaps other sports). Namely, admission by the players and teams that indeed there is a problem is what must occur before the sport takes a serious turn towards cleaning up.
Cycling and baseball both miss the boat in the 1990's
Mitchell identifies the turning point as sometime after the 1988 Summer Olympics when Ben Johnson tested positive. In fact there were many news reports during the 1990's about steroid use in baseball, and as early as 1988 many fans were already jeering Jose Canseco about his alleged steroid (ab)use. So the interesting thing is that as players' power increased and rumours began to make the rounds, baseball found itself in a similar position to pro cycling.
In the peloton during the 1990's the same thing was happening---average speeds were increasing, rumours were lurking, and the media suspected something was up. Admittedly, hindsight is 20/20, yet it is interesting that neither sport moved on these signs and "symptoms." Cycling introduced the 50% Hematocrit rule, which was pretty weak and easily manipulated, and baseball just ignored the problem for as long as it could.
And now the two sports find themselves in equally sticky situations. Wide scale and official reports (Mitchell's report in baseball, and The Operacion Puerto report in cycling) have torn open each sport and exposed its biggest stars.
And now. . .?
The fallout from the Mitchell report is still heavy and sinking in as more and more people read it and analyze its contents. At 409 pages, the full report is a handful, but the executive summary is an excellent place to start and anyone interested should definitely read it (it is only 40 pages). In the weeks and days to come still more bloggers and writers will weigh in on what all of this means, but one thing for certain is that Commissioner Bud Selig and MLB now go in to bat. This is their call to action, and we can only hope they choose to be courageous and think about the long term health of the sport.
As we said, at 409 pages this one is a handful, but join us this week as we try to pick it apart and look at the greater implications not just for baseball, but what something like this means for all of sports. Also, don't forget about the impending IAAF report on Oscar Pistorius, which we wil analyze in full and is due out any day now. Finally, we will run a short series on exercise in the cold, as the northern hemisphere winter is in full swing.
Stay with us for a busy couple of busy weeks ahead!
In the beginning many thought this was a fishing expedition of epic proportions, and was destined to return empty handed, or with only a few small time offenders. However in the end they landed a legend of baseball, the seven-time Cy Young winner Roger Clemens. Many other names were included in the report, and a history of drug use in baseball over the past 15 years is an important addition.
Also, on Sunday night Alex Rodriguez appeared in an interview on 60 Minutes, denying any drug use and also stating that he never once saw any illicit activity, although mentioning that there was always talk about it here and there.
Besides the players who were named in the report, the biggest loser is probably the Players Association. Mitchell states plainly that the association was "uncooperative" in many ways:
- Rejecting requests for relevant documents
- Granting only one interview with the executive director Donald Fehr
- Rejecting an interview request with the chief operating officer Gene Orza
- Denying a request to interview the director of a Montreal laboratory that analyzes samples
- Actively discouraged players from cooperating with Mitchell's investigation
"The problem is serious"
Ok, so tell us something we do not know! As obvious as Mitchell's statement sounds, it is an important step in this process. Yes, the pundits and bloggers would all agree, and have all been saying for a long time, that indeed the problem is serious. However we lacked the hard evidence and inside information to back this up. Mitchell's report now goes on the official record and we hope this leads to future steps in the right direction for baseball (and perhaps other sports). Namely, admission by the players and teams that indeed there is a problem is what must occur before the sport takes a serious turn towards cleaning up.
Cycling and baseball both miss the boat in the 1990's
Mitchell identifies the turning point as sometime after the 1988 Summer Olympics when Ben Johnson tested positive. In fact there were many news reports during the 1990's about steroid use in baseball, and as early as 1988 many fans were already jeering Jose Canseco about his alleged steroid (ab)use. So the interesting thing is that as players' power increased and rumours began to make the rounds, baseball found itself in a similar position to pro cycling.
In the peloton during the 1990's the same thing was happening---average speeds were increasing, rumours were lurking, and the media suspected something was up. Admittedly, hindsight is 20/20, yet it is interesting that neither sport moved on these signs and "symptoms." Cycling introduced the 50% Hematocrit rule, which was pretty weak and easily manipulated, and baseball just ignored the problem for as long as it could.
And now the two sports find themselves in equally sticky situations. Wide scale and official reports (Mitchell's report in baseball, and The Operacion Puerto report in cycling) have torn open each sport and exposed its biggest stars.
And now. . .?
The fallout from the Mitchell report is still heavy and sinking in as more and more people read it and analyze its contents. At 409 pages, the full report is a handful, but the executive summary is an excellent place to start and anyone interested should definitely read it (it is only 40 pages). In the weeks and days to come still more bloggers and writers will weigh in on what all of this means, but one thing for certain is that Commissioner Bud Selig and MLB now go in to bat. This is their call to action, and we can only hope they choose to be courageous and think about the long term health of the sport.
As we said, at 409 pages this one is a handful, but join us this week as we try to pick it apart and look at the greater implications not just for baseball, but what something like this means for all of sports. Also, don't forget about the impending IAAF report on Oscar Pistorius, which we wil analyze in full and is due out any day now. Finally, we will run a short series on exercise in the cold, as the northern hemisphere winter is in full swing.
Stay with us for a busy couple of busy weeks ahead!
Kamis, 13 Desember 2007
Running Economy Part III
Training techniques to improve economy (or should that be performance?)
Today sees the third and concluding part of our series on Running Economy. It's been a whistle stop tour of a complex subject. We have no doubt that we'll be returning to the topic in time, because it has major implications for how we understand fatigue and performance, but for now, we stuck to the boundaries - there is a lot to be written in the coming week! But hopefully today we'll provide some 'meat' that might help explain economy a little more, as well as provide some practical insights into how it can be improved.
On that note, there's a very valid question about whether you should worry about training specifically to improve your running economy, or whether good, common sense training just happens to improve economy as you do it.
I was out on a training run just yesterday, and have a 10 km loop that I do once in a while. Compared to about a month ago, when I just started running again after a layoff due to illness/injury, I covered the 10km a minute or so faster, running at the same effort level as before. And it occurred to me as I was jogging along that if I were to put on my scientist's hat (or lab coat, if you wish), I would probably find about four or five reasons to explain how I can run faster with the same level of effort - running economy would be one of them, for sure.
So in other words, scientists are sometimes very good at looking at the runner (or sportsman) after the fact and working out that X, Y and Z have changed, and that must explain the faster running, when all along, it's the simple fact that you've been running that explains it! Had I consciously spent the last month trying to improve my economy to help me get faster, chances are I'd only improve by the same amount anyway, or maybe even less!
The point is, sometimes the simplest solution is the best one, and that is the case with running economy. Over-complicating things by trying to target what we've emphasized is only one of many factors contributing to performance is likely to be a bit of a self-defeating task - rather just train, and let it happen!
The best way to improve running economy - just run!
Don't worry, that's not all we have to offer as practical advice for today! But it's the most obvious and truest statement we could make! When it comes to training, practice makes perfect. A great illustration was provided a few months ago when we were discussing Pose Running Technique, and we came across a study that looked at the oxygen cost of running in a group of athletes who had been taught Pose for 12 weeks.
What one would predict is that when learning a new running technique, the oxygen cost would go UP, because you'd be less economical as a result of doing a task that is relatively unfamiliar. And sure enough, that's what they found - running economy was worse when running Pose. A number of people wrote in and said this was expected, and that given more time (than the 12 weeks of training in the study), the Pose Runners would improve their economy. Maybe that's true (the debate about Pose was covered back then, you can link to the posts and read it), but the point is, within 12 weeks, economy was still worse.
Turning that around, it implies that regular running will improve economy. We don't often think of running as a task that requires co-ordination, timing, balance and motor control, but it most certainly is. If you ever want to see that in action, then you need to watch an elite runner training. They move differently from you and me (OK, from me - you may be one of them!). I remember standing track side as SA's Olympic Silver Medallist Mbulaeni Mulaudzi did some 300m repeats once, and being struck by the fact that he just moved differently - the flick of the heel during the swing, the arm carriage, knee drive etc. are all subtly different and I have little doubt that this neuromuscular control, while not exclusively responsible for performance, plays a big part, especially in distance runners. There are some other factors, which we'll touch on in a moment, that also contribute to this, though.
Endurance running - what do the studies show?
A couple of problems exist with the scientific literature on running economy. First, there are surprisingly few studies - remember, running economy was called the "forgotten" variable by one author (Carl Foster). Secondly, the initial level of fitness and ability of the runner plays a huge role, as I'm sure you can appreciate - a good runner needs very different training compared to a novice. So it's a little tricky to tease out the valuable information.
In general,however, research studies support that running economy improves with higher volume, slower running. So longer and slower distance training is more effective as a means to improve economy. The reasons for this include the increase in mitochondria, which means more effective use of oxygen by muscle. Also, it's been found that the longer and slower running eventually leads to a 'learned' neuromuscular response where the vertical oscillation of the runner is reduced. In otherwords, less time going up and down, more energy saved, and this is simply a function of repetition!
Now here's where things get tricky! Many of you are probably thinking "what about speed work?" Surely that will see massive improvements in running economy? There's always confusion about whether faster runners are more or less economical. And here, the general rule is that it follows what one might call The Law of Specificity, which basically says that you'll be good at what you train for! In otherwords, if you are a middle distance runner (800/1500m), then you'll be more economical at higher speeds than a marathon runner at those higher speeds. The interesting thing is that it's been found that this same middle distance runner then becomes less economical at the slower speeds than the marathon runner. So again, economy is good where you train it, which to me really re-inforces the value of training specifically, and how important co-ordination and motor control are!
So the take home message - if you're talking novice runners, with little running behind them, then any running will make a difference (as it did for me in the last month, I'm sure!). This is the point I made earlier - economy improves with fitness, and so any running is beneficial. But if it's performance you're after, and the very small improvements that make a big difference to performance (not just economy), then other forms of training become more critical. This also illustrates the complexity of training, and this is where we get into plyometrics and strength training.
Strength and plyometrics
Let's deal with strength training first. There is evidence that strength training improves running economy, probably because it improves the function of the neuromuscular system. In order to understand this, we first have to run through an admittedly basic introduction to an important concept known as the Stretch Shortening Cycle.
Basically, when you are running, a great deal of muscle activity occurs in the milliseconds BEFORE your foot lands on the ground. Why? Well, the muscle is 'pre-activating' in order to increase stiffness of the leg and joints ahead of landing. The stiffer muscle not only absorbs more shock, but it also helps the muscle-tendon unit to store more energy.
Think of the muscle-tendon as a spring. When you land, the muscle lengthens, in what is called an eccentric muscle contraction. As soon as you then push off, for what is called the concentric part of the running stride, you can 'harness' the energy that was stored when you landed. The concentric contraction is more powerful and more efficient, if it follows the eccentric contraction. It therefore uses less oxygen and energy to do the same job, or can do a better job. This is why if you want to jump up as high as possible (for example, to slam dunk a basketball), you bend down and then 'bounce' back up - you are taking advantage of what is known as the "Stretch-shortening cycle" to improve the performance of your jump.
The same goes for running, where this Stretch shortening cycle is critical to performance. The result of all this pre-activation and concentric-eccentric contraction is that the CONTACT TIME is reduced, and performance is improved. Fatigue during the course of a 5km time-trial has been shown to impair the ability of the muscle to "pre-activate", and the result is that your contact time with the ground goes up. Imagine a ball bouncing off a wall - if it gets softer and softer, it bounces off much more slowly, whereas a very stiff ball returns quickly (golf ball vs squash ball, for example).
How does this relate to running economy and strength?
Well, apart from the obvious theory which is that the muscle is stronger, the theory and evidence is that strength training improves running economy specifically because the contact time and reflexes that control the neuromuscular system are improved.
In particular, there is a type of training, known as PLYOMETRIC training that has been theorized to be very effective as a means for improvement of performance and running economy.
Plyometric training
Plyometric training is an explosive form of strength training, which uses drills like hopping, bounding, jumping, skipping and sprinting. During plyometrics, you are exaggerating the stretch shortening cycle, causing major eccentric and concentric training, and this helps to improve the efficiency of the whole system. The result is that the athlete is better able to store and use energy, and therefore the muscle can produce the same force (and hence running speed) with less energy demand, so VO2 goes down. Also, there is evidence that plyometrics increases the stiffness of joints, and stiffer joints are better able to store and release the energy, again saving the cost of running without sacrificing speed.
There is a very intriguing theory that African runners have a more developed, better functioning stretch shortening cycle that Europeans. Also, a Finnish scientist (Paavoleinen) found that plyometric training improved 5km time-trial performance by 3% (this was in quite good and highly-trained runners, so 3% is no laughing matter), which was associated with reduced contact times and running economy (8% lower).
Having said all this, beware of overdoing plyometrics as the "Secret weapon" for your training! The risk of injury is high, and so this should neither be tried out by novice runners, or done too often. It's a very effective method of training if done properly though. I certainly don't coach athletes without also using this kind of training, though it takes different forms, depending on the athlete - sometimes hill running is sufficient, whereas other times, you can get creative and come up with all sorts of drills, using hurdles, ropes, and your imagination! But again, not something that should be overdone...
Flexibility - you CAN be too flexible
The final component of training we look at is flexibility. There was a time when athletes were being drilled to do as much stretching as possible - failing to do so, we were told, would predispose you to injury. Well, injuries aside, there is evidence the being TOO flexible also negatively affects running economy, and thus possibly performance.
There is confusion about it though (as usual, I guess!). One study, for example, found that improving flexibility of the hip flexors and extensors(to lift the knee) resulted in better running economy. The argument here was that if you are flexible enough, and provided you have balance between left and right, front and back, then you need to do less work to balance and stabilize the body during running.
But then other research has found that being less flexible is better. In fact, more studies show that less flexible runners are more economical than the other way around. For example, from novice runners all the way to elite runners, it's been found that as the flexibility in the trunk (hips, and core muscles) and the legs improves, running economy is lower. Therefore, if you want to be economical, you'd err on the side of being inflexible!
The theory behind this option is far more believable to me. We've discussed how the stiffness and ability of the muscle to store and then release energy helps with running and reduces oxygen cost above. Now, the same goes for flexibility. If you are very flexible in the legs (especially the calf and ankle), then you need to do far more to stablize and store energy, and so it pays to be stiffer, less flexible.
As far as the core muscles and trunk go, the less flexible you are, the more stable the pelvis is, and the less muscle work is required to limit the motion as you run - you're a more 'compact unit' so to speak. To sum it up then - less flexibility means less work required for stability and also more elastic energy return from stiffer muscles and joints. I therefore tend to believe the theory that being less flexible is better for running.
Having said that, it doesn't mean that flexbility is not important. I hope it's quite clear that it's all about BALANCE. In other words, right vs. left, front vs. back balance (in both strength and flexibility) is what determines stability and thus possibly economy. The take home message is therefore to avoid random, indiscriminate stretching, because for all you know, you're messing up your natural balance, increasing injury risk and becoming less economical. But also, don't avoid stretching altogether, because then you might go the other way and get too tight in one important area! Everything in moderation!
Conclusion
So that's it for Part III, and the series. It's been a very interesting one, confirming the words of Carl Foster that running economy is a forgotten aspect of performance! It certainly seems that we have much to learn. The future of running research may be along the lines of the Tadese study that kicked off this series, and perhaps in a year or two, we'll understand much more what causes such remarkable running economy.
My personal feeling is that biomechanics, small calves and long legs aside, there is something critical that we can't quite measure. I am a big believer in the neuromuscular factors affecting performance. I believe that running economy is in fact a symptom of some underlying neuromuscular process or system that confers an advantage of certain runners. When you train, your neuromuscular system improves, you become more co-ordinated and your running economy improves, along with performance. But quite what this neuromuscular adaptation is (apart from the ones we've discussed) is not clear just yet. I feel it will go a long way to explaining the East African dominance in running and will also explain fatigue more comprehensively than any other theory.
So it's quite clear that we're not done with Running Economy! It will be back! We hope that this particular series has been interesting - we certainly haven't had the same debate, but it's a far less controversial topic than the muscle cramps and fluid ones!
Join us over the next few days as we scratch the surface of Baseball's Mitchell report and the report on Pistorius (which we hope is out soon)!
Ross
Today sees the third and concluding part of our series on Running Economy. It's been a whistle stop tour of a complex subject. We have no doubt that we'll be returning to the topic in time, because it has major implications for how we understand fatigue and performance, but for now, we stuck to the boundaries - there is a lot to be written in the coming week! But hopefully today we'll provide some 'meat' that might help explain economy a little more, as well as provide some practical insights into how it can be improved.
On that note, there's a very valid question about whether you should worry about training specifically to improve your running economy, or whether good, common sense training just happens to improve economy as you do it.
I was out on a training run just yesterday, and have a 10 km loop that I do once in a while. Compared to about a month ago, when I just started running again after a layoff due to illness/injury, I covered the 10km a minute or so faster, running at the same effort level as before. And it occurred to me as I was jogging along that if I were to put on my scientist's hat (or lab coat, if you wish), I would probably find about four or five reasons to explain how I can run faster with the same level of effort - running economy would be one of them, for sure.
So in other words, scientists are sometimes very good at looking at the runner (or sportsman) after the fact and working out that X, Y and Z have changed, and that must explain the faster running, when all along, it's the simple fact that you've been running that explains it! Had I consciously spent the last month trying to improve my economy to help me get faster, chances are I'd only improve by the same amount anyway, or maybe even less!
The point is, sometimes the simplest solution is the best one, and that is the case with running economy. Over-complicating things by trying to target what we've emphasized is only one of many factors contributing to performance is likely to be a bit of a self-defeating task - rather just train, and let it happen!
The best way to improve running economy - just run!
Don't worry, that's not all we have to offer as practical advice for today! But it's the most obvious and truest statement we could make! When it comes to training, practice makes perfect. A great illustration was provided a few months ago when we were discussing Pose Running Technique, and we came across a study that looked at the oxygen cost of running in a group of athletes who had been taught Pose for 12 weeks.
What one would predict is that when learning a new running technique, the oxygen cost would go UP, because you'd be less economical as a result of doing a task that is relatively unfamiliar. And sure enough, that's what they found - running economy was worse when running Pose. A number of people wrote in and said this was expected, and that given more time (than the 12 weeks of training in the study), the Pose Runners would improve their economy. Maybe that's true (the debate about Pose was covered back then, you can link to the posts and read it), but the point is, within 12 weeks, economy was still worse.
Turning that around, it implies that regular running will improve economy. We don't often think of running as a task that requires co-ordination, timing, balance and motor control, but it most certainly is. If you ever want to see that in action, then you need to watch an elite runner training. They move differently from you and me (OK, from me - you may be one of them!). I remember standing track side as SA's Olympic Silver Medallist Mbulaeni Mulaudzi did some 300m repeats once, and being struck by the fact that he just moved differently - the flick of the heel during the swing, the arm carriage, knee drive etc. are all subtly different and I have little doubt that this neuromuscular control, while not exclusively responsible for performance, plays a big part, especially in distance runners. There are some other factors, which we'll touch on in a moment, that also contribute to this, though.
Endurance running - what do the studies show?
A couple of problems exist with the scientific literature on running economy. First, there are surprisingly few studies - remember, running economy was called the "forgotten" variable by one author (Carl Foster). Secondly, the initial level of fitness and ability of the runner plays a huge role, as I'm sure you can appreciate - a good runner needs very different training compared to a novice. So it's a little tricky to tease out the valuable information.
In general,however, research studies support that running economy improves with higher volume, slower running. So longer and slower distance training is more effective as a means to improve economy. The reasons for this include the increase in mitochondria, which means more effective use of oxygen by muscle. Also, it's been found that the longer and slower running eventually leads to a 'learned' neuromuscular response where the vertical oscillation of the runner is reduced. In otherwords, less time going up and down, more energy saved, and this is simply a function of repetition!
Now here's where things get tricky! Many of you are probably thinking "what about speed work?" Surely that will see massive improvements in running economy? There's always confusion about whether faster runners are more or less economical. And here, the general rule is that it follows what one might call The Law of Specificity, which basically says that you'll be good at what you train for! In otherwords, if you are a middle distance runner (800/1500m), then you'll be more economical at higher speeds than a marathon runner at those higher speeds. The interesting thing is that it's been found that this same middle distance runner then becomes less economical at the slower speeds than the marathon runner. So again, economy is good where you train it, which to me really re-inforces the value of training specifically, and how important co-ordination and motor control are!
So the take home message - if you're talking novice runners, with little running behind them, then any running will make a difference (as it did for me in the last month, I'm sure!). This is the point I made earlier - economy improves with fitness, and so any running is beneficial. But if it's performance you're after, and the very small improvements that make a big difference to performance (not just economy), then other forms of training become more critical. This also illustrates the complexity of training, and this is where we get into plyometrics and strength training.
Strength and plyometrics
Let's deal with strength training first. There is evidence that strength training improves running economy, probably because it improves the function of the neuromuscular system. In order to understand this, we first have to run through an admittedly basic introduction to an important concept known as the Stretch Shortening Cycle.
Basically, when you are running, a great deal of muscle activity occurs in the milliseconds BEFORE your foot lands on the ground. Why? Well, the muscle is 'pre-activating' in order to increase stiffness of the leg and joints ahead of landing. The stiffer muscle not only absorbs more shock, but it also helps the muscle-tendon unit to store more energy.
Think of the muscle-tendon as a spring. When you land, the muscle lengthens, in what is called an eccentric muscle contraction. As soon as you then push off, for what is called the concentric part of the running stride, you can 'harness' the energy that was stored when you landed. The concentric contraction is more powerful and more efficient, if it follows the eccentric contraction. It therefore uses less oxygen and energy to do the same job, or can do a better job. This is why if you want to jump up as high as possible (for example, to slam dunk a basketball), you bend down and then 'bounce' back up - you are taking advantage of what is known as the "Stretch-shortening cycle" to improve the performance of your jump.
The same goes for running, where this Stretch shortening cycle is critical to performance. The result of all this pre-activation and concentric-eccentric contraction is that the CONTACT TIME is reduced, and performance is improved. Fatigue during the course of a 5km time-trial has been shown to impair the ability of the muscle to "pre-activate", and the result is that your contact time with the ground goes up. Imagine a ball bouncing off a wall - if it gets softer and softer, it bounces off much more slowly, whereas a very stiff ball returns quickly (golf ball vs squash ball, for example).
How does this relate to running economy and strength?
Well, apart from the obvious theory which is that the muscle is stronger, the theory and evidence is that strength training improves running economy specifically because the contact time and reflexes that control the neuromuscular system are improved.
In particular, there is a type of training, known as PLYOMETRIC training that has been theorized to be very effective as a means for improvement of performance and running economy.
Plyometric training
Plyometric training is an explosive form of strength training, which uses drills like hopping, bounding, jumping, skipping and sprinting. During plyometrics, you are exaggerating the stretch shortening cycle, causing major eccentric and concentric training, and this helps to improve the efficiency of the whole system. The result is that the athlete is better able to store and use energy, and therefore the muscle can produce the same force (and hence running speed) with less energy demand, so VO2 goes down. Also, there is evidence that plyometrics increases the stiffness of joints, and stiffer joints are better able to store and release the energy, again saving the cost of running without sacrificing speed.
There is a very intriguing theory that African runners have a more developed, better functioning stretch shortening cycle that Europeans. Also, a Finnish scientist (Paavoleinen) found that plyometric training improved 5km time-trial performance by 3% (this was in quite good and highly-trained runners, so 3% is no laughing matter), which was associated with reduced contact times and running economy (8% lower).
Having said all this, beware of overdoing plyometrics as the "Secret weapon" for your training! The risk of injury is high, and so this should neither be tried out by novice runners, or done too often. It's a very effective method of training if done properly though. I certainly don't coach athletes without also using this kind of training, though it takes different forms, depending on the athlete - sometimes hill running is sufficient, whereas other times, you can get creative and come up with all sorts of drills, using hurdles, ropes, and your imagination! But again, not something that should be overdone...
Flexibility - you CAN be too flexible
The final component of training we look at is flexibility. There was a time when athletes were being drilled to do as much stretching as possible - failing to do so, we were told, would predispose you to injury. Well, injuries aside, there is evidence the being TOO flexible also negatively affects running economy, and thus possibly performance.
There is confusion about it though (as usual, I guess!). One study, for example, found that improving flexibility of the hip flexors and extensors(to lift the knee) resulted in better running economy. The argument here was that if you are flexible enough, and provided you have balance between left and right, front and back, then you need to do less work to balance and stabilize the body during running.
But then other research has found that being less flexible is better. In fact, more studies show that less flexible runners are more economical than the other way around. For example, from novice runners all the way to elite runners, it's been found that as the flexibility in the trunk (hips, and core muscles) and the legs improves, running economy is lower. Therefore, if you want to be economical, you'd err on the side of being inflexible!
The theory behind this option is far more believable to me. We've discussed how the stiffness and ability of the muscle to store and then release energy helps with running and reduces oxygen cost above. Now, the same goes for flexibility. If you are very flexible in the legs (especially the calf and ankle), then you need to do far more to stablize and store energy, and so it pays to be stiffer, less flexible.
As far as the core muscles and trunk go, the less flexible you are, the more stable the pelvis is, and the less muscle work is required to limit the motion as you run - you're a more 'compact unit' so to speak. To sum it up then - less flexibility means less work required for stability and also more elastic energy return from stiffer muscles and joints. I therefore tend to believe the theory that being less flexible is better for running.
Having said that, it doesn't mean that flexbility is not important. I hope it's quite clear that it's all about BALANCE. In other words, right vs. left, front vs. back balance (in both strength and flexibility) is what determines stability and thus possibly economy. The take home message is therefore to avoid random, indiscriminate stretching, because for all you know, you're messing up your natural balance, increasing injury risk and becoming less economical. But also, don't avoid stretching altogether, because then you might go the other way and get too tight in one important area! Everything in moderation!
Conclusion
So that's it for Part III, and the series. It's been a very interesting one, confirming the words of Carl Foster that running economy is a forgotten aspect of performance! It certainly seems that we have much to learn. The future of running research may be along the lines of the Tadese study that kicked off this series, and perhaps in a year or two, we'll understand much more what causes such remarkable running economy.
My personal feeling is that biomechanics, small calves and long legs aside, there is something critical that we can't quite measure. I am a big believer in the neuromuscular factors affecting performance. I believe that running economy is in fact a symptom of some underlying neuromuscular process or system that confers an advantage of certain runners. When you train, your neuromuscular system improves, you become more co-ordinated and your running economy improves, along with performance. But quite what this neuromuscular adaptation is (apart from the ones we've discussed) is not clear just yet. I feel it will go a long way to explaining the East African dominance in running and will also explain fatigue more comprehensively than any other theory.
So it's quite clear that we're not done with Running Economy! It will be back! We hope that this particular series has been interesting - we certainly haven't had the same debate, but it's a far less controversial topic than the muscle cramps and fluid ones!
Join us over the next few days as we scratch the surface of Baseball's Mitchell report and the report on Pistorius (which we hope is out soon)!
Ross
Rabu, 12 Desember 2007
Oscar Pistorius research
Results on Oscar Pistorius due - but will they provide answers?
As we mentioned above, it's a big couple of days for long-awaited reports. First, there is the Mitchell report, which was mentioned in our other post today, and which we'll analyse over the coming days. Then second, there's a report from the IAAF on whether Oscar Pistorius should be allowed to compete against able bodied athletes.
This has been one of the more controversial topics of discussion in the sports sciences this year, and we had some excellent discussion on it earlier this year when we wrote about the results of their first analysis on Pistorius, and then later when we analyzed all of the available evidence in this case. (You can find all the posts looking him up as a key word in the right hand column of the page). We had some scathing comments and lively discussion, although we haven't yet cut off our own legs to prove the argument, as someone suggested.
Our position is unequivocally that the carbon-fibre blades confer a large advantage. We acknowledge the disadvatanges he has, and recognize his character and determination (but these are separate issues), but we tried to lay out a number of arguments in the lead up to Pistorius' first race against able-bodied athletes in Europe earlier this year. Our prediction, made on the basis of the physiological arguments we had discussed, was that Pistorius would not show the normal decline in running speed as the race progressed. In contrast, if the opposing view was true (that Pistorius has no advantage), then he would show the normal slowing down during the 400 m race, or an even greater slowing down than most runners, because of the supposed loss of energy caused by the prosthetic limbs.
Sure enough, when he ran in Rome, he got faster and faster as the race went on, never showing the progressive reduction in speed that occurs in ALL elite 400 m races. These results that have never been seen before in an elite 400m race, not even from the greatest 400m runners ever - Johnson and Wariner included. So based on that, I felt that the IAAF had sufficient evidence to prevent his taking part. But in their wisdom, they decided they should do more and so came up with I will politely describe as an absolutely bizarre battery of tests. We will discuss these tests in detail once the report is released (assuming the tests are made available and we don't have to rely on the journalists and press releases), but they included:
Will the tests show anything?
There are some good tests here, but I'm equally tempted to invite everyone to watch as the IAAF paint themselves into a corner. Because quite frankly, these tests have some potentially serious flaws - the measurement of oxygen consumption during a supra-maximal bout lasting only 45 seconds is one such problem. The interpretation of the data gathered poses a real problem, whichever way it is concluded.
For example, let's say that the testing finds that Pistorius has a lower VO2 during his 400m time-trial, and that his lactate levels are lower. What do they do with that information? Do they ban him because of the lower VO2, which shows less oxygen demand and possible advantage? Or do they let him run because his VO2 is lower, which some might suggest indicates that doesn't have the same ability to use oxygen as a result of having less muscle mass? Is it a disadvantage or an advantage? Depends on your point of view!
Look also at lactate - first of all, they will measure venous lactate, which means the interpretation is limited to begin with. But what do they do if Pistorius has lower lactate levels that the other runners? Do they let him run because there's no evidence lactate is even important (a fundamental, basic assumption that the IAAF scientists have somehow gotten wrong), or do they ban him because he doesn't produce as much lactate and must therefore have an advantage (a flawed argument yet again)?
My point is, no matter what the results, there will be a "valid" scientific argument from both sides, and these tests will conclude little (apart from test 6). The measurement of VO2 is near impossible to interpret for such a short, high intensity running bout. The only tests that might contribute to the definite outcome are the mechanical tests (number 6 in the list). The rest are, to be a little more blunt, a fishing expedition, and may prove useless.
Bottom line - the IAAF had the result they needed - a never seen before 400 m race where he sped up when everyone else was slowing down. He defied physiological possibility, and it was clear that he was unique, and it could have, should have been the end of it.
But, let's see what the testing shows. Whatever happens, it should make for some interesting discussion!
But first, the Mitchell report!
As we mentioned above, it's a big couple of days for long-awaited reports. First, there is the Mitchell report, which was mentioned in our other post today, and which we'll analyse over the coming days. Then second, there's a report from the IAAF on whether Oscar Pistorius should be allowed to compete against able bodied athletes.
This has been one of the more controversial topics of discussion in the sports sciences this year, and we had some excellent discussion on it earlier this year when we wrote about the results of their first analysis on Pistorius, and then later when we analyzed all of the available evidence in this case. (You can find all the posts looking him up as a key word in the right hand column of the page). We had some scathing comments and lively discussion, although we haven't yet cut off our own legs to prove the argument, as someone suggested.
Our position is unequivocally that the carbon-fibre blades confer a large advantage. We acknowledge the disadvatanges he has, and recognize his character and determination (but these are separate issues), but we tried to lay out a number of arguments in the lead up to Pistorius' first race against able-bodied athletes in Europe earlier this year. Our prediction, made on the basis of the physiological arguments we had discussed, was that Pistorius would not show the normal decline in running speed as the race progressed. In contrast, if the opposing view was true (that Pistorius has no advantage), then he would show the normal slowing down during the 400 m race, or an even greater slowing down than most runners, because of the supposed loss of energy caused by the prosthetic limbs.
Sure enough, when he ran in Rome, he got faster and faster as the race went on, never showing the progressive reduction in speed that occurs in ALL elite 400 m races. These results that have never been seen before in an elite 400m race, not even from the greatest 400m runners ever - Johnson and Wariner included. So based on that, I felt that the IAAF had sufficient evidence to prevent his taking part. But in their wisdom, they decided they should do more and so came up with I will politely describe as an absolutely bizarre battery of tests. We will discuss these tests in detail once the report is released (assuming the tests are made available and we don't have to rely on the journalists and press releases), but they included:
- Running 400m on an outdoor track with maximum effort and VO2 test with K4 mask. Blood lactate was then measured – four times in first 10 minutes, after 30 minutes, 1 hour and four hours.
- Body scanning to take anthropometric data
- Running sub-max speed in the indoor lab. Data recorded by 12 cameras, 4 force plates and 4 high-speed cameras. Oscar ran 5 repetitions of about 80 metres.
- WINGATE test on static bicycle to measure lactate
- Max VO2 test also done on static bike
- Mechanical testing was also made of both foot modules – swing frequency, pendulum frequency with foot module hanging and attached at the upper connection point
Will the tests show anything?
There are some good tests here, but I'm equally tempted to invite everyone to watch as the IAAF paint themselves into a corner. Because quite frankly, these tests have some potentially serious flaws - the measurement of oxygen consumption during a supra-maximal bout lasting only 45 seconds is one such problem. The interpretation of the data gathered poses a real problem, whichever way it is concluded.
For example, let's say that the testing finds that Pistorius has a lower VO2 during his 400m time-trial, and that his lactate levels are lower. What do they do with that information? Do they ban him because of the lower VO2, which shows less oxygen demand and possible advantage? Or do they let him run because his VO2 is lower, which some might suggest indicates that doesn't have the same ability to use oxygen as a result of having less muscle mass? Is it a disadvantage or an advantage? Depends on your point of view!
Look also at lactate - first of all, they will measure venous lactate, which means the interpretation is limited to begin with. But what do they do if Pistorius has lower lactate levels that the other runners? Do they let him run because there's no evidence lactate is even important (a fundamental, basic assumption that the IAAF scientists have somehow gotten wrong), or do they ban him because he doesn't produce as much lactate and must therefore have an advantage (a flawed argument yet again)?
My point is, no matter what the results, there will be a "valid" scientific argument from both sides, and these tests will conclude little (apart from test 6). The measurement of VO2 is near impossible to interpret for such a short, high intensity running bout. The only tests that might contribute to the definite outcome are the mechanical tests (number 6 in the list). The rest are, to be a little more blunt, a fishing expedition, and may prove useless.
Bottom line - the IAAF had the result they needed - a never seen before 400 m race where he sped up when everyone else was slowing down. He defied physiological possibility, and it was clear that he was unique, and it could have, should have been the end of it.
But, let's see what the testing shows. Whatever happens, it should make for some interesting discussion!
But first, the Mitchell report!
Mitchell Report due today
Former Senator's report promises to be a 'huge story'
Eighteen months ago, former US Senator George Mitchell launched a probe into steroid use in baseball. The probe is the result of an unprecedented shake-up in Major League Baseball that started as far back as 1998, when reporters noticed a tub of androstenedione in aspiring home run champ Mark McGwire's locker. McGwire went on to hit 70 homers that season, smashing the former record of 61. According to San Francisco Chronicle reporters Mark Fainaru-Wada and Lance Williams in their book Game of Shadows, this helped spur Barry Bonds to begin using steroids in pursuit of McGwire's new record (and fame).
For the next few years things were relatively quiet in baseball, until all hell broke loose in September 2003 when Victor Conte's BALCO offices were raided. We all know the resulting shockwaves that went through sports, and we still feel it---in October Marion Jones finally confessed to using drugs, and just this week she was finally stripped of her Sydney 2000 medals.
In March 2005 congress invited a number of players, former players, and baseball executives to a hearing to discuss drug use in their sport. Most parties decline, however, leading congress to issue subpoenas, which were fought hard by MLB. Former players like McGwire and Jose Canseco were dragged in front of congress for eleven hours, although most refused to provide any meaningful information. Said McGwire, "My lawyers have advised me that I cannot answer these questions without jeopardizing my friends, my family or myself. I intend to follow their advice." That was unfortunate as McGwire (and others) had a golden opportunity to come clean. He had already retired, and all that was on the line was his records, which were illegitimate anyway.
Fast forward another year to March 2006, when the former Senator Mitchell agrees to lead an investigation into alleged steroid use by players working with Conte's BALCO. However baseball commissioner Bud Selig makes it known that Mitchell has the authority to expand the investigation as he sees fit.
But don't we know they are all juicing anyway?
And now, 1.5 years later, the Mitchell's findings and report will be released. . .but will it just tell us what we already know? We have a feeling that most of The Science of Sport's readers will agree that MLB has an endemic drug problem. Since 2003 and the BALCO bust numerous names have been named, and even since MLB's (weak) testing policy was instituted in 2003 a few players have had multiple violations. But Mitchell's report should go deeper than and perhaps outline for us the depth of the use. To date no big names have tested positive, and sources today promise that Mitchell's work will expose just how high up the drug use goes. Stay tuned for our analysis of the findings as we will be glued to the media outlets and waiting for the release.
Preview of other forthcoming attractions
Apart from the Mitchell Report, there are a few other big "events" on the horizon. First, speaking of release dates, Part III of our series on Running Economy will be "released" tomorrow here at The Science of Sport. We plan to cover training effects on running economy with some practical applications. We are sure all the media outlets will pick it up. . .!
And then also due out tomorrow is the IAAF's report on Oscar Pistorius, which we will analyze in great depth. But there is a preview of the tests that were done and our initial impressions of them above. Those who've been with us since June will have read the controversy regarding Oscar Pistorius, which culminated in a series of tests to determine whether his carbon fibre blades do give him an advantage. Given the tests that they performed, which basically amounted to science's equivalent of a fishing expedition, it might make for interesting dicussion! We'll be sure to bring you as much insight as possible!
In the mean time, check out this complete time line of drug use in baseball since 1998 to refresh your memory and fill in some blanks.
For the next few years things were relatively quiet in baseball, until all hell broke loose in September 2003 when Victor Conte's BALCO offices were raided. We all know the resulting shockwaves that went through sports, and we still feel it---in October Marion Jones finally confessed to using drugs, and just this week she was finally stripped of her Sydney 2000 medals.
In March 2005 congress invited a number of players, former players, and baseball executives to a hearing to discuss drug use in their sport. Most parties decline, however, leading congress to issue subpoenas, which were fought hard by MLB. Former players like McGwire and Jose Canseco were dragged in front of congress for eleven hours, although most refused to provide any meaningful information. Said McGwire, "My lawyers have advised me that I cannot answer these questions without jeopardizing my friends, my family or myself. I intend to follow their advice." That was unfortunate as McGwire (and others) had a golden opportunity to come clean. He had already retired, and all that was on the line was his records, which were illegitimate anyway.
Fast forward another year to March 2006, when the former Senator Mitchell agrees to lead an investigation into alleged steroid use by players working with Conte's BALCO. However baseball commissioner Bud Selig makes it known that Mitchell has the authority to expand the investigation as he sees fit.
But don't we know they are all juicing anyway?
And now, 1.5 years later, the Mitchell's findings and report will be released. . .but will it just tell us what we already know? We have a feeling that most of The Science of Sport's readers will agree that MLB has an endemic drug problem. Since 2003 and the BALCO bust numerous names have been named, and even since MLB's (weak) testing policy was instituted in 2003 a few players have had multiple violations. But Mitchell's report should go deeper than and perhaps outline for us the depth of the use. To date no big names have tested positive, and sources today promise that Mitchell's work will expose just how high up the drug use goes. Stay tuned for our analysis of the findings as we will be glued to the media outlets and waiting for the release.
Preview of other forthcoming attractions
Apart from the Mitchell Report, there are a few other big "events" on the horizon. First, speaking of release dates, Part III of our series on Running Economy will be "released" tomorrow here at The Science of Sport. We plan to cover training effects on running economy with some practical applications. We are sure all the media outlets will pick it up. . .!
And then also due out tomorrow is the IAAF's report on Oscar Pistorius, which we will analyze in great depth. But there is a preview of the tests that were done and our initial impressions of them above. Those who've been with us since June will have read the controversy regarding Oscar Pistorius, which culminated in a series of tests to determine whether his carbon fibre blades do give him an advantage. Given the tests that they performed, which basically amounted to science's equivalent of a fishing expedition, it might make for interesting dicussion! We'll be sure to bring you as much insight as possible!
In the mean time, check out this complete time line of drug use in baseball since 1998 to refresh your memory and fill in some blanks.
Interesting news from the marathon
The sub 2-hour marathon, London 2008, and Paula gets hot
We're bang in the middle of our series on Running Economy, but thought that for today, we'd take a break from that series and turn our attention to a few interesting news stories that are coming out of the world of marathon running.
The Sub-2 hour marathon: Debate re-opened
The first is a discussion about whether a sub-2:00 marathon will ever be run? This is a topic that hit headlines in September this year, when Haile Gebrselassie broke Paul Tergat's world record in the marathon. The margin? 29 seconds, taking the time down from 2:04:55 (run by Tergat four years before) to 2:04:26. We covered the race, and Geb's splits and pacing in a couple of articles at the time.
As tends to happen whenever a barrier is broken, everyone started talking about the prospects of the sub 2-hour marathon. Even Gebrselassie made his predictions, though he was a little more circumspect, suggesting instead that he would run 2:03 some day. But a lot of people were looking even further into the distance, at the 2-hour barrier. And a recent report from the Herald paper quotes Dave Bedford, London Marathon organizer, as predicting that the 2:02 will be run by 2015, and a sub-2 hour time will come in 20 years!
The problem is that even a basic analysis of the world record in the last twenty to thirty years suggests that this talk is likely a touch premature! For example, in the last 22 years, the marathon record has come down by just under 3 minutes, from 2:07:12 in 1985 (Carlos Lopes) to the current 2:04:26. So for Bedford to be correct, we need the next 22 years to yield 50% more than this - 4:30! But even more than this, since Ronaldo da Costa broke Dinsamo's 10-year old record in 1998, we've moved into an era where the record is coming down by seconds, not minutes, making this highly unlikely!
In otherwords, it's difficult to see how anyone is going to knock more than 30 seconds off this time. When Gebrselassie ran his 2:04:26, we all marvelled at how massively he 'shattered' the record, people calling it a once in a lifetime run! And that was for just 29 seconds - in other words, we "only" need another nine performances just like that, and we'll have our sub-2 hour marathon! Now, how often do we expect a runner to line up and smash 30 seconds off a world record? And then of course, the ceiling effect comes into play as well, and says that once we get to the 2:02 range, it will become even more difficult.
I hear some of you saying "What about a Paula-esque performance? She took it down by 2 minutes!". And of course, this may yet happen. But just looking at Gebrselassie's pacing from this world record, you'll see that he is incredibly consistent. That suggests to me that he's right on the limit, because if he had any reserve, you'd see that through fluctuations in pace especially at the end (this is one possible interpretation, I acknowledge that). But given the fact that he took 29 seconds off the time running this kind of race, it's difficult to see how he's going to get 3 seconds/kilometer to get the time down to 2:02. As it was, he was already right on the limit.
So my feeling is that the 2:02 will eventually come, but it won't be by 2015, and a sub-2 hour time will certainly not happen with anyone from the current crop.
As for who is likely to break the world record next, my money would be on Zersenay Tadese, ahead of Bekele. A lot of people are getting hyped up over Bekele and his chances of running 2:02, but I suspect Tadese will be the dominant marathon runner from the current generation of track stars. Time will tell...
The London 2008 Marathon and some implications for the Olympics
Speaking of Dave Bedford and the London Marathon, his marathon predictions might be a little debatable, but one certainly would not want to argue the quality of the field he puts together for the London Marathon!
You can read some of the names here, but the big one is Martin Lel, defending champion and New York champ. Regular readers will know that I'm a huge fan of Lel's, I think he's the complete package, so it was with mixed feelings that I read that he's signed up for London, and that he's currently leading the lucrative World Marathon Majors series.
Why mixed feelings? Because his presence in London, combined with what must be a growing incentive to win a share of the $1 million prize purse means he is thus less likely to compete in Beijing in peak shape, if at all. No word on that yet, but I had really hoped for a race between him and Gebrselassie for the Olympic title - the best Racer in the world against the fastest marathon runner in history, would have been a great clash!
As for Gebrselassie, he is not on London's books yet, but there was talk that he might yet be signed. I seriously doubt it, because he's already running the Dubai Marathon in mid-January. If he then runs London in April, and is aiming for the Marathon in Beijing, that equals one tough year. I know I'd be advising against it, but stranger things have happened...I certainly would lengthen the odds on Gebrselassie if he runs in all three those races.
But it's a bumper field for London, Olympic and World Champions, racers, fast men, strong men, the works. And so the Marathon year will certainly get off to a great start, first with Geb in Dubai and then this field. Let's hope it is as good as the year that has just gone (we'll do a look back at the science and physiology of the year's marathons next week in our "Year in Review" series).
Paula gets hot - in South Africa
Finally, it was with interest that I read this article on Paula Radcliffe and the UK athletics team coming out to my home country, South Africa, for a training camp in January next year. The purpose of the camp is to help the athletes prepare for the Beijing heat and to help them figure out what to drink in Beijing. There are a couple of reasons why this is interesting.
One, it shows that the UK are serious about preparing for the heat, because the plan is to bring out three physiologists to help the athletes figure out their best hydration strategies. They are talking about measuring the salt and sugar content of the sweat in order to help the athletes figure out the optimal hydration strategies.
Regular readers of The Science of Sport will know that we think the best hydration strategy is to drink when you're thirsty! You can read our rationale for this in our series on fluid intake (link on the right of the page) and our series on Muscle Cramps. And it's a lot cheaper than flying athletes out for a training camp! But dodgy science practices aside, I think that this type of camp has as much a psychological benefit as it does physiological. In my experience, athletes benefit when they believe that they have done everything possible to prepare for their event, regardless of whether what they are doing actually works! And so the camp idea will certainly help, because from the article, the athletes are buying in.
One thing it will not do is help the athletes prepare for the heat - it's too far out, and they are only coming in for 10 days. So having achieved some degree of adaptation to the heat, they'll then fly back to cold and wet England and undo it all by mid-February. So the purpose is a planning, rather than a physiological one.
From a scientific point of view, there some pretty large potential potholes. For one thing, each athlete is coming out to South African for only 10 days. We know that with the body's adaptation to the heat, the sodium content of the sweat changes quite dramatically (sweat becomes more dilute). This adaptation takes about 6 days to be achieved, so let's hope the UK physiologists are at least aware of this, and don't make their "proven" recommendations based on the sweat content in the first few days! The values they get in the last few days will be very different from those in the first few! And so if they do this, the UK athletes will just about be drinking sea-water in Beijing!
Secondly, the venue they have chosen (Potchefstroom - a town close to where I grew up), is hardly comparable to Beijing. It has a typical temperature of 25 degrees, and humidity is next to nothing - think dry, and relatively mild heat. Compare Beijing, which will be like a greenhouse meets a steam bath! So I'm not convinced that they are replicating conditions as well as they might. There are two follow-up camps planned, however, and so they probably have this covered.
The other big issue, of course, is that state of training is a critical determinant of both sweat rate and sodium loss in sweat. And so therefore, one would expect the requirements in August (at the Olympics) to be very different from what they are in January, even without the additional factor of the heat! So I see great complications coming!
Again, it just re-inforces the point that because the body is so well designed, so balanced and "intelligent", it can change the amount of salt lost in the sweat depending on heat adaptation and training. So why introduce a third person (or even a second person physiologist), who simply cannot hope to understand the integration of the physiology during exercise as well as the human body can? It is a case of losing sight of the wood for the trees, and over-complicating matters.
From a practical perspective, what constitutes a successful drinking pattern? Is it the fluid intake routine that keeps the body weight the same? Is it keeping the body's salt content the same? Are you trying to keep the core temperature down? Fluid intake doesn't help this to begin with, and we know that most athletes lose weight during the course of the marathon. One thing that I will predict is that if Paula Radcliffe tries to drink so much that she doesn't lose any weight during the race, she'll never win the Olympic Gold medal - she'll be too busy worrying about stomach cramps and nausea to race properly!
Bottom line - drink to thirst. Of course, the idea to practice drinking before Beijing is a good one, and I think it would be a good exercise to allow athletes to exercise with a range of options - high sodium, low sodium, high glucose, low glucose etc., and then see which they find easiest to drink. Because if it tastes too salty to the athelte, then it probably is! The wonders of the intelligent body...
Join us again tomorrow for Part III in the series on Running Economy!
Ross
We're bang in the middle of our series on Running Economy, but thought that for today, we'd take a break from that series and turn our attention to a few interesting news stories that are coming out of the world of marathon running.
The Sub-2 hour marathon: Debate re-opened
The first is a discussion about whether a sub-2:00 marathon will ever be run? This is a topic that hit headlines in September this year, when Haile Gebrselassie broke Paul Tergat's world record in the marathon. The margin? 29 seconds, taking the time down from 2:04:55 (run by Tergat four years before) to 2:04:26. We covered the race, and Geb's splits and pacing in a couple of articles at the time.
As tends to happen whenever a barrier is broken, everyone started talking about the prospects of the sub 2-hour marathon. Even Gebrselassie made his predictions, though he was a little more circumspect, suggesting instead that he would run 2:03 some day. But a lot of people were looking even further into the distance, at the 2-hour barrier. And a recent report from the Herald paper quotes Dave Bedford, London Marathon organizer, as predicting that the 2:02 will be run by 2015, and a sub-2 hour time will come in 20 years!
The problem is that even a basic analysis of the world record in the last twenty to thirty years suggests that this talk is likely a touch premature! For example, in the last 22 years, the marathon record has come down by just under 3 minutes, from 2:07:12 in 1985 (Carlos Lopes) to the current 2:04:26. So for Bedford to be correct, we need the next 22 years to yield 50% more than this - 4:30! But even more than this, since Ronaldo da Costa broke Dinsamo's 10-year old record in 1998, we've moved into an era where the record is coming down by seconds, not minutes, making this highly unlikely!
In otherwords, it's difficult to see how anyone is going to knock more than 30 seconds off this time. When Gebrselassie ran his 2:04:26, we all marvelled at how massively he 'shattered' the record, people calling it a once in a lifetime run! And that was for just 29 seconds - in other words, we "only" need another nine performances just like that, and we'll have our sub-2 hour marathon! Now, how often do we expect a runner to line up and smash 30 seconds off a world record? And then of course, the ceiling effect comes into play as well, and says that once we get to the 2:02 range, it will become even more difficult.
I hear some of you saying "What about a Paula-esque performance? She took it down by 2 minutes!". And of course, this may yet happen. But just looking at Gebrselassie's pacing from this world record, you'll see that he is incredibly consistent. That suggests to me that he's right on the limit, because if he had any reserve, you'd see that through fluctuations in pace especially at the end (this is one possible interpretation, I acknowledge that). But given the fact that he took 29 seconds off the time running this kind of race, it's difficult to see how he's going to get 3 seconds/kilometer to get the time down to 2:02. As it was, he was already right on the limit.
So my feeling is that the 2:02 will eventually come, but it won't be by 2015, and a sub-2 hour time will certainly not happen with anyone from the current crop.
As for who is likely to break the world record next, my money would be on Zersenay Tadese, ahead of Bekele. A lot of people are getting hyped up over Bekele and his chances of running 2:02, but I suspect Tadese will be the dominant marathon runner from the current generation of track stars. Time will tell...
The London 2008 Marathon and some implications for the Olympics
Speaking of Dave Bedford and the London Marathon, his marathon predictions might be a little debatable, but one certainly would not want to argue the quality of the field he puts together for the London Marathon!
You can read some of the names here, but the big one is Martin Lel, defending champion and New York champ. Regular readers will know that I'm a huge fan of Lel's, I think he's the complete package, so it was with mixed feelings that I read that he's signed up for London, and that he's currently leading the lucrative World Marathon Majors series.
Why mixed feelings? Because his presence in London, combined with what must be a growing incentive to win a share of the $1 million prize purse means he is thus less likely to compete in Beijing in peak shape, if at all. No word on that yet, but I had really hoped for a race between him and Gebrselassie for the Olympic title - the best Racer in the world against the fastest marathon runner in history, would have been a great clash!
As for Gebrselassie, he is not on London's books yet, but there was talk that he might yet be signed. I seriously doubt it, because he's already running the Dubai Marathon in mid-January. If he then runs London in April, and is aiming for the Marathon in Beijing, that equals one tough year. I know I'd be advising against it, but stranger things have happened...I certainly would lengthen the odds on Gebrselassie if he runs in all three those races.
But it's a bumper field for London, Olympic and World Champions, racers, fast men, strong men, the works. And so the Marathon year will certainly get off to a great start, first with Geb in Dubai and then this field. Let's hope it is as good as the year that has just gone (we'll do a look back at the science and physiology of the year's marathons next week in our "Year in Review" series).
Paula gets hot - in South Africa
Finally, it was with interest that I read this article on Paula Radcliffe and the UK athletics team coming out to my home country, South Africa, for a training camp in January next year. The purpose of the camp is to help the athletes prepare for the Beijing heat and to help them figure out what to drink in Beijing. There are a couple of reasons why this is interesting.
One, it shows that the UK are serious about preparing for the heat, because the plan is to bring out three physiologists to help the athletes figure out their best hydration strategies. They are talking about measuring the salt and sugar content of the sweat in order to help the athletes figure out the optimal hydration strategies.
Regular readers of The Science of Sport will know that we think the best hydration strategy is to drink when you're thirsty! You can read our rationale for this in our series on fluid intake (link on the right of the page) and our series on Muscle Cramps. And it's a lot cheaper than flying athletes out for a training camp! But dodgy science practices aside, I think that this type of camp has as much a psychological benefit as it does physiological. In my experience, athletes benefit when they believe that they have done everything possible to prepare for their event, regardless of whether what they are doing actually works! And so the camp idea will certainly help, because from the article, the athletes are buying in.
One thing it will not do is help the athletes prepare for the heat - it's too far out, and they are only coming in for 10 days. So having achieved some degree of adaptation to the heat, they'll then fly back to cold and wet England and undo it all by mid-February. So the purpose is a planning, rather than a physiological one.
From a scientific point of view, there some pretty large potential potholes. For one thing, each athlete is coming out to South African for only 10 days. We know that with the body's adaptation to the heat, the sodium content of the sweat changes quite dramatically (sweat becomes more dilute). This adaptation takes about 6 days to be achieved, so let's hope the UK physiologists are at least aware of this, and don't make their "proven" recommendations based on the sweat content in the first few days! The values they get in the last few days will be very different from those in the first few! And so if they do this, the UK athletes will just about be drinking sea-water in Beijing!
Secondly, the venue they have chosen (Potchefstroom - a town close to where I grew up), is hardly comparable to Beijing. It has a typical temperature of 25 degrees, and humidity is next to nothing - think dry, and relatively mild heat. Compare Beijing, which will be like a greenhouse meets a steam bath! So I'm not convinced that they are replicating conditions as well as they might. There are two follow-up camps planned, however, and so they probably have this covered.
The other big issue, of course, is that state of training is a critical determinant of both sweat rate and sodium loss in sweat. And so therefore, one would expect the requirements in August (at the Olympics) to be very different from what they are in January, even without the additional factor of the heat! So I see great complications coming!
Again, it just re-inforces the point that because the body is so well designed, so balanced and "intelligent", it can change the amount of salt lost in the sweat depending on heat adaptation and training. So why introduce a third person (or even a second person physiologist), who simply cannot hope to understand the integration of the physiology during exercise as well as the human body can? It is a case of losing sight of the wood for the trees, and over-complicating matters.
From a practical perspective, what constitutes a successful drinking pattern? Is it the fluid intake routine that keeps the body weight the same? Is it keeping the body's salt content the same? Are you trying to keep the core temperature down? Fluid intake doesn't help this to begin with, and we know that most athletes lose weight during the course of the marathon. One thing that I will predict is that if Paula Radcliffe tries to drink so much that she doesn't lose any weight during the race, she'll never win the Olympic Gold medal - she'll be too busy worrying about stomach cramps and nausea to race properly!
Bottom line - drink to thirst. Of course, the idea to practice drinking before Beijing is a good one, and I think it would be a good exercise to allow athletes to exercise with a range of options - high sodium, low sodium, high glucose, low glucose etc., and then see which they find easiest to drink. Because if it tastes too salty to the athelte, then it probably is! The wonders of the intelligent body...
Join us again tomorrow for Part III in the series on Running Economy!
Ross
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