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Sunday, April 06, 2008

Paris Marathon Report and splits

Tsegaye Kebede - a name for the future, as the spring marathon season starts with a bang

The spring marathon season has begun! As Jonathan wrote earlier this week, the next month throws up a number of big European marathons, as well the famed Boston Marathon (April 21st).

That will be a big focus for us over the next while, starting today, which saw the first of those races – the Paris Marathon. Paris has always been something of a “poor cousin” to the London Marathon, by virtue of its proximity to that race – London is next week and bagged most of the world’s marathon superstars.

Paris Marathon – victory for Kebede, sending notice to the world

However, Paris did still attract a quality, competitive field, demonstrated by the final performances.

1. Tsegaye Kebede (ETH) - 2:06:40

2. Moses Arusei (KEN) - 2:06:50

3. Hosea Rotich (KEN) - 2:07:24

The winning time was 2:06:40, and the table below shows how that time was put together (based on splits as reported by race broadcaster).

How the race unfolded

The early pace was consistent, just outside 3:00/km, which was exactly as requested by race organizers. A very large group developed, led by the pacemakers, and halfway was reached in 63:41 by a group of between 15 and 20 runners. Between 21 and 25km, athletes began peeling off the back, and the group was stretched out despite the pace actually slowing. However, it's worth noting that many were in territory they’d never been in before, running at a pace that was, for some, up to four minutes faster than their previous bests!

The next five kilometres, from 30 to 35km, is where marathon races are often won or lost, but the pace remained consistent at just outside 3:00 min/km. It was enough to cut the lead group from about twelve to eight men. It was therefore a race of attrition, more a case of last man standing at one pace than a race with attacks, at least up to this point.

At 35km, Moses Arusei of Kenya, a man who came into the race with a PB outside 2:10, threw in a surge and the group was stretched out, and then broken. Only three men were able to follow this pace, including Hosea Rotich and Tsegaye Kebede, the Ethiopian. Arusei was the slowest of the men in that lead group of three, but he continued to drive the pace at the front. He surged again a few minutes later, and Rotich was put into difficulty at the back.

The race finish - speed wins the day for Kebede

Arusei and Kebede of Ethiopia then ran through the final 5km alone. An odd couple – about 20 cm difference in height, with the diminutive Kebede reminiscent of Ethiopia's Miruts Yifter, and at only 45kg, one of the lightest men on the circuit – they reached 40km in 2:00:20, which means the last 5km had been covered in 14:37 – that was the split that did the damage to the lead group, 2:55/km over the last 5km.

Kebede, aged only 21, has a speed pedigree that would frighten many marathon runners – a 59:35 half marathon earlier this year, and as regular readers of our site will know, that speed is perhaps the biggest predictor of success over the longer distance.

Just before 41km, Kebede kicked on and soon opened a gap of about 10m over the brave, but by now somewhat outpaced, Arusei. It was the race’s decisive move. With about 500m to go, there was a noticeable jump in pace as Kebede surged again. As the table above shows, the final 2km were covered at an average pace of 2:53.1/km. The finish time? 2:06:40. It was fast, but not quite fast enough to break the course record, which was missed by a mere 7 seconds! You'll see from the table above that until the move of Arusei at 35km, they were never on for a sub-2:07 clocking, and it took a 2:55/km average pace from 35km onwards to gave us the mid-2:06 finish! So a remarkable, but ultimately insufficient ramp in pace in the final 5km.

That meant Kebede missed out on a course record bonus, but he did still bag a 50,000 Euro purse, and perhaps more importantly, is now a name to notice on the global marathon scence. 21 years old, a sub-60 minute half marathon and a 2:06 marathon in a tactical race! Remember the name – Tsegaye Kebede.


Women’s race - gutsy racing and a win for Martha Komu of Kenya


Unfortunately, we didn’t get too many splits from the women’s race, particularly early on. The halfway split was however given and it was 72:03, which projected a finish time in the low 2:24’s.

Given that most of today’s major marathons are being won in the low 2:20’s, that’s not a bad pace, especially considering that there were no pace-makers for the women’s field (officially organized pacemakers – there was the presence of a number of men who provided “pacing” suport) and that the five women in the lead group were not low 2:20-caliber athletes – most had never broken 2:30 before this race.

30 km was reached in 1:43:13, projecting a finish time of 2:25:10. The pace had therefore slowed to 3:30 min/km, which was not all that surprising given that the athletes were running many minutes faster than they’d ever run before.

A small group of five became two, when Martha Komu of Kenya and Tola Workness of Ethiopia moved clear.

Komu wins the award for bravery on the day - a 2:33 runner, she did most of the work to create this break of two athletes, and in the final 5 km, her face was a picture of pain as she ran into unchartered marathon territory. Her arms were flying in every direction, her style had fallen to pieces, but she hung in there. Tola moved clear with about 500m to race, looking completely comfortable, but Komu fought back and coming into the final straight, actually moved passed the more favoured Tola!

Tola was unable to respond, and in the end, the race was won by Martha Komu in 2:25:29, beating the more favoured Tola and the clock. Her previous best was 2:32:45, and so she set a PB by an astonishing 7 minutes, 16 seconds! Extra-ordinary, and probably the run of the day, though the "breakthrough" of Kebede probably has longer-lasting implications for the marathon world!

Looking ahead – a “taster” for London

Paris, for all its qualities (the city and race), is a taster of what we can expect come next Sunday, when the very best runners in the world line up on the other side of the Channel in London. It’s the deepest, highest quality marathon field put together anywhere in the world, and the racing should be incredible. It includes Martin Lel, who is the great marathon racer of the last four years. We’ll preview the race this week, followed by full coverage next Sunday.

Ross

Thursday, April 03, 2008

The swimsuit debate

Technology in sport: The swimsuit debate continues, as Adidas enters the fray

Welcome to the Science of Sport!
Be sure to visit our main page where we have daily analysis
and comment of the swimming and other events at Beijing 2008!

Those of you who have been following our swimming posts over the last few weeks will have read a series of articles looking at the Speedo LZR swimsuit and the controversy it has caused.

In the third post of that series, we mentioned that the other swimsuit makers would soon be unleashing their own high-tech designs onto the swimming world. That began with Arena and their Powerskin R-Evolution (right), which has the distinction (for the meantime) of being the only suit other than a Speedo in which a world record has been set this year (by Pelligrini of Italy!).

The Adidas "entry" - The Powerweb

The latest suit to hit the waters is the Adidas TechFit Powerweb suit, shown in the picture below right. The suit was first used in the ongoing British swimming trials in Sheffield.

What makes this suit "unique" are the Thermoplastic Urethane (TPU) "powerbands" which are placed at strategic positions on the suit. These bands, made of an elastic material that compress the muscle beneath them, are supposed to improve blood flow and explosive power. This will, according to Adidas, provide a "slingshot that helps to propel the swimmer from the blocks and off the wall at turns".

Note that Adidas are emphasizing quite a different strategy from that adopted by Speedo and Arena, which have reported how they have altered the hydrodynamics and movement through the water - body shape and drag, particularly. Adidas no doubt does the same (they'd be foolish not to, given the large effect this clearly has on performance), but they have emphasized the Powerbands as a distinctive feature, which I find interesting.

I don't know whether their claims can be verified, but if they are that effective, we might be able to see swimmers shooting off the walls of Beijing and gaining places over their not so fortunate Adidas-clad rivals! Or is it that simple? I stress again, my expertise lies in running and cycling, not swimming, and so I am certainly not the best person to answer my own question. However, I would love to see a study in Beijing of swimmers and just how much time is gained (or lost) in the turns, and at the start. This would of course not prove that the suit is to blame (or credit), since numerous other factors are involved in these technique-oriented variables, but it would make for interesting reading if swimmers in one suit all happened to demonstrate superior turn ability.

The other difference that Adidas brings to the pool is the world's first breaststroke specific suit. According to reports, breaststroke specialists were complaining that the generic suit had the Powerweb bands in the wrong places, restricting their stroke. And so a breaststroke suit was designed specially for that event. Again, it interests me to know just how large the advantage may be, if any exists at all? Do Adidas-wearing breaststrokers derive so much benefit that we might notice a difference? Are we talking tenths-of-a-second, or milliseconds?

The suit makers are all claiming "revolutionary" improvements in performance - they even named the suit R-evolution in the case of Arena - and so if true, then simple observation and description of performance may well throw up some interesting observations. I'm really hopeful that come Beijing, the manufacturers will have all developed their suits to the point where the margins between them are so tiny as to be insignificant. We might then see world records falling like tenpins, but in competitive races, which is the least that can be hoped for!

The debate continues - are they swimmers or muscle-powered yachts?

In any event, we've already had the debate over whether the technology is good or bad for the sport, and whether it should be legal. And as has been pointed out, one can only paint oneself into the proverbial corner by doing that! Because of course, equipment is as much part of the sport as training and so one can hardly return to the good old days of Alexander Popov (right), who amazingly didn't ever bother with either a swim cap or a full length suit (they weren't around yet) when he was in his prime! It was his 50 m freestyle record that was being swopped between Sullivan and Bernard this year, and I wonder if he'd still be smiling had he been wearing an LZR or a R-evolution?

On a more serious note, I read an interesting thing on this blog on the Arena research and development of their latest swimsuit...

It turns out that one of the lead researchers in the development of this suit is a scientist named Alfio Quarteroni. He was one of the scientists who was responsible for computer models and simulations on Alinghi, which is the Swiss yacht that won the America's cup in 2003 and 2007. As most will know, yachting is not dissimilar to Formula 1 racing when it comes to innovation and technology, and no stone is left unturned to design boats that have minimal drag in the water.

And so, the scientist's job with Arena was presumably to do very much the same thing - work out how to reduce drag and improve speed by altering shape and water flow over the "yacht/body". Now, we clearly are not going to resolve this issue, but it's worth discussing - at what point does swimming move over into the realm of yachting? At the risk of sound absurd, does the advance in technology narrow the gap between swimming and yachting, to the point where the swimmer is analogous to a human-powered (as opposed to wind-powered) yacht?

I'm not against technology, and as I've said before, I have no problem with these suits, provided the playing field (or water, in this case!) is level and all have equal access. I'm not 100% convinced this will happen, but nevertheless, I don't see the swimsuits as a bad thing. But it just struck me the other day that when swimmers look for milliseconds, they seem to search in the same place as engineers on America's Cup yachts. Is that sport? Of course, the cost of innovation is vastly different - $700 for a swimsuit hardly compares to millions for a yacht.

And then, they are still powered by physiology, of course, which is a big difference. And swimmers can (and should be) spending hours a day working on their starts, turns and body position in the water. Then there is propulsion from muscle contraction that can't be discounted, however low the drag is. And no suit is going to turn me, a regular splasher, into anything like an Olympic hopeful. But if it makes 5% difference, would that be revolutionary enough to move a semi-final hopeful onto the podium? Just some random thoughts...

Ross

Wednesday, April 02, 2008

Marathon season is upon us!

Spring races loom on near horizon

As some of us slog through the last vestiges of the northern hemisphere winter, the spring marathon season approaches. Being an Olympic year adds to the excitement as many Olympic hopefuls will use a spring marathon to gauge their preparation. We have focused quite a bit on more technical posts recently, and with the racing season approaching we will take a turn towards more performance analysis. Let's take a look at what this spring will offer!

London has become legendary due to the intensely competitive fields they compile, while Paris has long been relegated as a second-tier race with a less competitive field, in spite of having "IAAF Gold Label Road Race" status. Having said that, however, it did have 35,000+ starters last year and nearly 27,000 finishers. The racing in France is this weekend (6 April) but does not see any big names toeing the line for the 25,000 Euros up for grabs. If the male winner breaks 2:11:45 and if the female winner breaks 2:23:15 that purse doubles to 50,000 Euros, which interestingly is not very different from the prize money and bonuses on offer at London.

The field for Paris reads like a "who's who" of second-tier races. Only two runners Takaoka Toshinari and Tola Tesfeye have sub-2:07 performances. None has a major marathon victory, although Toshinari was third in Chicago 2002 (2:06:13) and Joseph Ngolepus was third in London 2003 (2:07:57). The top five starters have PB's within 90 s of each other, so perhaps it could be a competitive race? As a side note, the organizers of the Paris Marathon are Amaury Sport Organisation, or ASO, who also organize the Tour de France and a number of other big French sporting events.

London brings the guns. . .again

Although Rotterdam is also on 13 April, something tells us that most eyes, including ours, will be focused on the racing in London. Yet again the organizers have assembled an incredible field. Those who are committed and still in the race include:

  • Felix Limo (KEN), 2:06:14, 2006 race champion
  • Emmanuel Mutai (KEN), 2:06:29, 2007 ING Amsterdam Marathon champion
  • Sammy Wanjiru (KEN), 2:06:39, 2007 Fukuoka Marathon winner; half-marathon world record holder
  • Martin Lel (KEN), 2:06:41, defending champion/2005 race champion and 2007 NYC champion
  • Hendrick Ramaala (RSA), 2:06:55, 2004 ING NYC champion
  • Jaouad Gharib (MAR), 2:07:02, two-time world champion
  • Stefano Baldini (ITA), 2:07:22, 2004 Olympic Marathon gold medalist
  • Yonas Kifle (ERI), 2:07:34, 2005 World Half-Marathon Championship bronze medalist
  • Abderrahim Goumri (MAR), 2:07:44, 2007 NYC and London runner-up
  • Ryan Hall (USA), 2:08:24, U.S. Olympic Marathon Trials champion
  • Luke Kibet (KEN), 2:08:52, 2007 world champion
  • Aleksey Sokolov (RUS), 2:09:07, 2007 adidas Dublin Marathon winner
  • Meb Keflezighi (USA), 2:09:53, 2004 Olympic Marathon silver medalist
Noticably absent are Paul Tergat and Haile Gebrselassie, although this field still contains proven champions from a number of high-level races. Admittedly runners like Ramaala and Baldini have not done much since their big years of 2004 when Baldini won gold in Athens and Ramaala won the NYC marathon, but Lel has proved to be perhaps the best tactical marathoner ever while Goumri has lost to him twice last year and surely represents a threat. And we cannot exclude Gharib, either, who lost to Ivuti on the line in Chicago last year and also is a two-time world champion.

We will get stuck into a more detailed preview next week when the final media guide for this year's race is released, so be sure come back for a more detailed analysis then.

Rotterdam

For the record, Rotterdam is also being run on Sunday, 13 April, and the organizers claim to have assembled the best field the race has ever seen. It includes five athletes with sub-2:07 PB's and six more who have run better than 2:08:
  • Robert Cheboror (Kenya) 2.06.23, 2004 Amsterdam champion
  • William Kipsang (Kenya) 2.06.39, 2003 Amsterdam champion
  • Paul Kiprop Kirui (Kenya) 2.06.44, 2006 Rotterdam runner-up
  • Richard Limo (Kenya) 2.06.45, 2007 Amsterdam runner-up
  • Driss el Himer (France) 2.06.48 Paris (4) 06-04-2003
  • Joshua Chelanga (Kenya) 2.07.05 Berlin (3) 26-09-2004
  • Benjamin Maiyo (Kenya) 2.07.09 Chicago (2) 09-10-2005
  • Salim Kipsang (Kenya) 2.07.29 Berlin (3) 30-09-2007
  • Rodgers Rop (Kenya) 2.07.32 Hamburg (1) 29-04-2007
  • Francisco Javier Cortez (Spain) 2.07.48 Hamburg (2) 22-04-2001
  • Jimmy Muindi (Kenya) 2.07.50 Rotterdam (1) 10-04-2005
  • Daniel Kipkoech Yego (Kenya) 2.08.16 Roma (3)13-03-2005
  • Solomon Bushendich (Kenya) 2.08.52 Amsterdam (1) 15-10-2006
  • Elijah Chemwolo Mutai (Kenya) 2.09.27 Chunchon (1) 23-10-2005
  • Daniel Rono (Kenya) 2.09.36 Toronto (2) 30-09-2007

While London's field has outpaced Rotterdam's in recent years, we should not forget that not too long ago Rotterdam held the World Record for the marathon and attracted the fastest runners. It is truly a fast course that can produce exciting racing.

112th Boston Marathon

Following London and Rotterdam by one week is the historical Boston Marathon. Again, we will save the in-depth preview for later, but suffice to say here that the notable entries on the men's side are 2007 Chicago champion Patrick Ivuti and 2006 Chicago and Boston champion Robert Cheruiyot.

Moving into May we will see the African Champs, which surely will be an important event for countries such as Kenya and Ethiopia as they make final Olympic selections, and then in June we see the start of the IAAF Golden League. By then we will be stuck into full Olympic mode, and every race will be an important indicator of who is showing form or not in the pre-Beijing run up.

For now please keep the debate and discussion going on running technique. It has been lively and very interesting so far, and join us next week for the full London preview!

Tuesday, April 01, 2008

Running technique: The Footstrike

Heel vs. Midfoot vs. Forefoot: How do elite runners land?

I've finally gotten around to this post, which is probably two weeks in the making, and it follows on from our recent series on running shoes. That series began by looking at whether shoes are in fact as much a cause of injury as a cure, and then evolved into a discussion of how the running market is evolving. Twenty years ago, it was all about motion-control shoes preventing overpronation to prevent injury. Today, it's all about running "barefoot in your shoes", as companies try to go back to "natural" without selling you "the Emperor's clothes", in effect! (It's quite a long post, my apologies, but a lot of important information to get through...)

The next logical question is to ask how is the foot supposed to land during running? This question evolves out of the discussion of shoes. vs barefoot running, and is often at the heart of discussions on running technique. Very often, debates of "technique" tend to start from the feet, jump to the knees ("lift your knees") and then skip to the arms, and that's about it! We won't go into too much detail on technique today, focusing instead on only one of many aspects - the landing of the foot, and particularly, whether the elite runners tend to land on the heel, the midfoot, or the forefoot.

Elite runners footstrike patterns

Perhaps surprisingly, there are very few studies looking at elite runners and footstrike patterns during actual races. Despite this, until recently, the overwhelming majority of coaches and experts were advocating that heel-striking was the most effective technique, simply because most athletes did it. That claim will come up again, but the perception that it was most effective has, over the last few years, been changing. And with the advent of Pose and other running techniques, as well as the observation that not all elite runners are landing on the heel first, people have now begun to advocate that forefoot landing is better! So we have this 180 degree shift, often in the absence of any substantial data to support the claim.

I am sure that many will have seen this kind of assertion (this one is from Wikipedia):

Leaning forward places a runner's centre of mass on the front part of the foot, which avoids landing on the heel and facilitates the use of the spring mechanism of the foot. In other words, landing on the heel is bad, to be avoided...
Or there is this, from Gordon Pirie (admittedly somewhat older):
"Running equals springing through the air, landing elastically on the forefoot with a flexed knee..."
But what is "better"? Where science has yet to catch up with opinion

It's important at this point to ask the very pertinent, but infrequently asked question: "What does 'better' mean?". In other words, when people are advocating that it's 'better' to land on the forefoot, what do they mean? Is it faster? More efficient? Less injury-prone? The fact is, the word "better" is used without studies specifically looking at any single one of these aspects. And the 'prudence concept', as applied to science, says that you cannot say something is "better" unless it's been studied and compared to the alternatives. Unfortunately, the science lags behind in this regard.

So for example, above you have the quote that you are supposed to land elastically on the forefoot. That implies performance and efficiency, which might be true for short exercise, lasting a minute or two. But in an event like the marathon, are we sure it remains the "better" option? If you went out and ran 2 hours today, landing on your forefoot instead of landing as you've always done, what would be the likely outcome? Chances are, you'd be hurting for a few days, with calf muscles that you had perhaps forgotten you had! Worst case scenario, you'd be injured for months with an Achilles tendon injury. That is certainly not a desirable outcome. So there are problems with making sweeping statements about landing patterns.

But more than this, these kinds of statements are never grounded in proof. So for example, when it's written that you land "elastically", has anyone ever done the study of elastic energy return in different types of running? They haven't, but there is theory about it, and that's where these recommendations come from. So the approach in the discussion that follows is for me to adopt the role of "questioner", playing Devil's Advocate, with the humble admission that science simply does not know the right answer, only the possibilities...

Looking at one particular study - elite 21 km runners

So in the current climate where real evidence is scarce and opinions hold sway, let's take a look at one study that has examined footstrike patterns during running events. It was done in 2004 in Japan, and published in 2007 in the Journal of Strength of Conditioning (not sure of the reason for the delay - it happens sometimes in science!). The full reference, for those interested, is Hasegawa et al., J Strength & Cond., 2007, (21), 888-893

It was performed at the 2004 Sapporro International Half Marathon in Japan. The scientists set up a high speed camera (very important for accurate collection of information - beats YouTube science any day!) at the 15km mark of the race, and captured most of the runners coming through. In total, they were able to observe the foot strike of 248 men and 35 women, and characterize them as either heel-strikers, mid-foot or forefoot strikers. They also measured Ground Contact Time at the 15km point.

The finding - what do you expect?

Before giving their main finding away, take a moment to guess what they would have found...If you are anything like me, and have read the substantial amount on the internet and in books about how it's "better" (there's that word again) to land on your forefoot, then of course, your expectation might be that they found:
  • The majority of runners land on the forefoot
  • Those that DO NOT land on the forefoot are the runners who finish towards the back of the field
Well, if that's what you thought, you'd be completely incorrect...! Because the finding is the following:
  • The vast majority (75%) of the elite runners land on the heel
  • About 1 in four (24%) runners landed on the mid-foot
  • Only 4 out of 283 runners landed on the forefoot
Those runners that landed on the forefoot did not finish in the first four positions, so the common argument (a flawed one) that the best athletes are forefoot strikers is not supported by this finding.

Possible conclusions - how you read the study is influenced by what you wish to prove...

So, given this, one is tempted to say that the landing of the foot makes no difference to overall performance. Of course, this is not necessarily true. As I wrote above, science is often taken out of context, and this is one such example. You cannot, for example, rule out the possibility that these heel-strikers might be a few seconds or minutes faster if they just learned to land on their forefoot! Personally, I think that's highly unlikely, and what is more likely is that they'll end up in rehab for Achilles injuries, but even that is a "bald assertion", based only on opinion!

Now, however, here is where it gets interesting, and this is where the forefoot advocates got quite excited. When the researchers divided the finishers into groups of 50, they started to see something of a change in mid-foot landing as you moved further down the list. In otherwords, there was a higher percentage of midfoot strikers in the first 50 runners than in the second, and then third, and so on. The graph below shows this for heel-strikers and mid-foot strikers (I haven't shown forefoot, because it's so tiny and insignificant by comparison):

At first glance, the conclusion from this graph is that if you want to be a faster runner, finishing higher up in the overall order, then you should be a midfoot striker, not a heel-striker. That's how many people interpreted the finding. And this may well be true. Unfortunately, there is another possible reason it looks like it does - perhaps it's simply a function of running faster.

Speed and footstrike

In otherwords, you naturally shift your contact point with the ground further forward when you run faster. The average speed, incidentally, of the first 50 runners was 3 minutes 3 seconds per kilometer. The second group of 50 runners averaged 3 minutes 10 seconds per kilometer. Hardly a big difference, but given the range (the 50th runner is at least a minute behind the 1st runner), is it possible that groups of 50 is too big, and that all this "finding" represents is a speed effect on footstrike?

The point is, this study does not allow you to differentiate between three possibilities:
  1. Faster runners are midfoot strikers (could be co-incidence or some other cause); or
  2. Midfoot strikers are faster runners (and therefore we should all change our running style and land on the front part of the foot more); or
  3. All runners would eventually be midfoot strikers, if they just ran fast enough!
This is another classic example of how a scientific result can be taken out of context and applied to give advice that may not be 100% correct.

Personal opinion and implications of this study

My personal reaction to this research, when it came out, was that it disproved the popular theory that all runners should be aiming to become midfoot or forefoot strikers. Most of us (well, I'm in this group, apologies if you are not) are nowhere near the elite level, and we're often told by experts and coaches that the elite are landing on the ball of the foot or the midfoot, and so we should too.

But the next time you think of running like Gebrselassie and trying to land mid or forefoot, consider this: if you go out and sprint 100m, you're likely to run on your toes the whole way - because you're running faster, you land more on the mid-foot, or even the forefoot.

Sprinting as you are, you'll probably cover 100m in 14 seconds, which puts you only 1 second ahead of a Bekele or a Gebrselassie in a 5000m race, so is it any wonder they are midfoot strikers on the track - they're running as fast as most of us sprint? The point I'm trying to make is, if you ran the speed they did, you'd be a mid-foot striker too! But just as I suspect they change as they slow down, we all do. So why, and on what basis, should you try to run with the same foot strike when you are running perhaps 3 minutes per kilometer SLOWER than them? Again, these are relatively bald assertions, but hopefully you recognize the implication of speed on foot strike.

So when you go out and run a 3 hour, or a 4 hour marathon, that's another story altogether. And what the Pose running study at UCT showed me a few years ago is that if you change the landing of the foot, you predispose the athlete to injury - that study took a group of runners and within two weeks had them all running on the midfoot (please don't write in to say that Pose doesn't mean midfoot, because Romanov was the coach and he was happy with their technique!). Two weeks later, they all broke down with Achilles tendon injuries!

Why? Because sitting where you are right now, if I was to walk into your office or your home and take you outside and ask you to please run landing on your forefoot or midfoot, I can pretty much guarantee that the way you would achieve this is to point your toe down...you're probably doing this as you read this - contract the calf, and point your toe away from your body, like in ballet. Now imagine your body weight landing on that contracted calf muscle 85 times a minute for 4 hours. That, simply put, is a recipe for disaster.

However, if you can gradually change your landing, then I do believe that you can shift your footstrike. But it's a gradual process. And more important, what is the point? There is no evidence that heel-strikers are injured more, no evidence that mid-foot runners are faster and perform better than heel-strikers, and so the ultimate question is:

Why would you want to change your foot landing to begin with? Science has little to offer you in support of this. And so my advice, having read this far (well done!), is to forget about the possibility that you're landing "wrongly", and just let your feet land where, and how they land, and worry about all the other things you can when you run!

If there is one thing you change in your running, don't focus on your footstrike, but rather on WHERE your feet land relative to your body. Because if you are over-reaching and throwing your foot out in front of you, that's a problem, but what happens when the rubber meets the road is less relevant!

I'm sure there's more to this topic, based on your questions and comments. As usual, fire away! And remember the humble admission from earlier - science, believe it or not, does not know the answer definitively! (just as we can't tell you why Bekele is so dominant in World X-Country!)

Ross

Late edit to the post - the comments section of the post has been closed (29 Aug 2009) - too many comments flying in to respond (on top of the other 20 posts still getting comments! And I don't want to ignore people!)

I would recommend that you click on "Running technique" in the tabs at the top of the page, and read through those posts to get the full picture and context to this post