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Wednesday, March 05, 2008

Running shoes continued

Running shoes and injuries: Debate continued

Yesterday, we did a short post looking at the debate around running shoes, and whether the shoes which claim to reduce injury risk are in fact part of the problem! Thanks to everyone for the spirited input on the debate - it's been lively and interesting so far. I thought it better to respond in a new post and perhaps lead the discussion based on those comments than bury my response in the Comments section to that post.

Another study on expensive shoes - money doesn't buy you comfort

First, thanks to Clyde for providing the link to the article from BJSM. You can find the article abstract here if you would like to read it. I have a copy of the article as well, and it makes for some interesting reading.

Basically, the researchers set out to evaluate three differently priced running shoes:

  • Expensive - priced over 70 Pounds (around $140 or R1100)
  • Medium price - around 60 Pounds ($120 or R900)
  • Low cost - 40 Pounds ($80 or R600)
The shoes were evaluated primarily on the basis of pressure under the foot and comfort, which is a subjective rating. So they didn't really tackle the issue of motion-control/anti-pronation devices, which is a pity (but more on that later).

Their findings? As you probably might have guessed based on Clyde's comments and the general trend, there were no differences between the shoes for either of these two factors - the cheap shoes produce the same pressure (cushioning), and the same perception of comfort as the expensive shoes. The difference in price of R500, then, results in little difference in terms of cushioning or comfort or pressure distribution.

In a follow up letter to this article, the reasons for this were pointed out - it's simply not feasible to change pressure by shoe-design, because the result would be a dramatic change in biomechanics - the analogy would be to switch from running on tarmac to running on soft, spongy sand. So in effect, the above-mentioned study was "doomed" to find no difference anyway. And of course, this might be true, but then it introduces the obvious question - if shoes can't change the pressure/cushioning, why the enormous price difference? And that's where the debate leads next...

What is missing - research on the 'gadgets'

This study is interesting in that it evaluates one aspect of running shoe design - pressure or cushioning. However, it fails to tackle what I believe is the bigger source of "controversy" around the shoe industry - all the gadgets and gimmicks that are inserted to provide MUCH NEEDED support to runners who over-pronate.

And a good many of the comments to our previous article are from runners who do pronate and have had experience in these shoes. Basically, the premise for these shoes is that upon landing, excessive pronation, which refers to the rolling in motion of the ankle (called eversion of the foot), is responsible for injury, since the pressures and loads placed on the shins and knees is excessively high. Therefore, control the pronation and you control the injury risk...

So shoe companies have all developed their own unique devices to do this. Apart from the devices that are proposed to aid with cushioning (Nike Air, Asics Gel, Adidas Adiprene, and so on), I would dare say that most of the product (and price) differentiation takes place with regards to these motion-control devices. Yet so little research has been done on them. Well, let me qualify that - there is "overwhelming evidence" on all of them, but they're done exclusively by the shoe companies and never published! The funny thing is, I can almost guarantee that one company will have research that proves their device superior, while another, having done almost identical research, will conclude that theirs is the best available!

So it's hardly surprising that Dr Richards and most of you writing into this post are suggesting that anti-pronation shoes are being over-emphasized, and that a well-cushioned shoe is the way to go.

My personal take on the issue - it's the training, not shoes

So let me take that one step further and actually put my head on the block on this one. I fully agree with that assessment - I don't believe that huge, heavy anti-pronation shoes are the solution for running injuries. I stated yesterday that if I were advising an athlete with injury problems, I'd look first, second, and third at their training, and then start to consider their footwear! The point is, training errors are responsible for injury, the rest is detail!

Of course, factors like biomechanics, muscle strength or flexibility imbalances are contributing factors, and so if a runner is "biomechanically correct" (incidentally, that term is thrown around with freedom but without a clear definition of what it actually means! But that's another issue!), they will get away with training that would cause injury to someone who is not so fortunate. Body size and weight are key factors, and then of course, you get leg length discrepancies that throw off alignment, making some people far more susceptible to injury - the result is that one person's ideal programme is another's "boot camp", guaranteed to break them down in a few weeks!

However, I don't believe that simply changing the shoe is the solution - changing the training, and gradually increasing the load is far more likely to resolve the injury.

At the two extremes (high arches or very flat feet), I believe that orthotics may be helpful. I myself have very flat feet (I could probably walk on water if I tried, and certainly on snow!) and I've been in orthotics before. However, I found they caused more problems than they resolved - super rigid, stiff and heavy. So I eventually ditched them, went back to the drawing board as far as training goes (did I mention that I believe training is the key to injury?), and basically started running as a beginner again - I spent a month doing a walk-run programme, consisting of 5 minutes jogging, 2 minutes walking, and eventually managed to phase out the walking part, and the problems are a thing of the past. And all in a pair of very well cushioned, neutral shoes. I certainly lie on the far end of the pronation continuum, but I really am convinced that given the right training, anyone can wear neutral shoes. I don't believe that buying a super-expensive motion control shoe will improve your chances, rather look at orthotics if you feel you have to obtain some support.

To sum up - when you buy your shoes, try them on for comfort and cushioning and fit, and once you find what works, then stick with it. But don't commit to the 'gadgets', well cushioned is sufficient.

The future of the shoe industry

Finally, if I may put on my marketing hat for a moment, I would predict that the heavy motion-control shoe will one day become an extinct species - it may already be on the endangered list! It's difficult to know what stimulated the massive growth in the area, but I suspect what happened was that in the 1970's, when the running "boom" hit, a good many people with "less than perfect" biomechanics took up running. And of course, marketing is all about meeting people's NEEDS. And when the NEED doesn't exist, then you simply create it - "science" is often a big help in this regard!

So the companies recognized that perhaps a million people who never ran before were now running and this represented a huge market to be tapped into. But they needed a selling point, and Point of Differentiation, and the "combat overpronation" campaign was just the ticket!

Now, in 2008, I feel the opposite is happening. More and more people are talking about barefoot running, which is probably a little too extreme, a case of over-compensation, perhaps. But the point is, there is a shift in the market, and I'm sure the companies will respond and try to create a new need - I suppose they already have, with the barefoot shoe concept. But all this adds up to the beginning of the end for the heavy, anti-pronation shoe, which will probably become a relic in the next 20 years. But then again, those may be famous last words!

Thanks again for the debate, keep it coming!

Ross

22 Comments:

Paul said...

Thanks for putting up some interesting information! I have gone from being a injured heel striking runner to a mid/forefoot runner. I found that orthotics and cushioned supportive shoes gave me more problems. I also have very high arches.

I think that extra cushioning limits your ability to sense the road (trail). This leads to a longer foot strike and more time on the ground. Hence more pronation and higher chance for injury.

Now I exclusively run in 6 oz or lighter racing flats and sometimes the five fingers. One interesting trend is that over time my feet have shrunk a quarter size as my foot muscles have become stronger.

Keep up the good reporting!

Ross Tucker and Jonathan Dugas said...

Hi Paul

Thanks for the experience. You are right in theory about excess cushioning affecting stride mechanics, though I must confess that I'm not familiar with any research on the effects of cushioning of typically available shoes on contact time. Certainly, if you take a page out of the sprinter's spike, the shoe is very stiff and rigid, the idea being that any loss of energy on the track equals loss of speed. Even tartan athletics tracks are designed with minimal cushioning/bounce to aid sprinting.

However, once you get to the typical running shoe, I'm not sure that they are ever cushioned enough to cause the athlete to become "stuck" to the ground, so to speak. In theory, it's true that this would happen, but in the letter I have linked to in this post, the author makes this point. If anyone knows of that research on cushioning and contact times, please let me know. But my feeling is (and experience) that in the normal range of running shoes, it won't make too much difference.

As for the orthotics, I totally agree with you there, as I said. My experience with orthotics was not very good at all. And I know many peole you have had the same experience as you, with a switch to a lightweight shoe fixing them up - perhaps in 30 years' time, that's the only shoe we'll be able to buy!

Thanks for the positive feedback!
Ross

TriExpert said...

Gentlemen,

I've long been a proponent of running in minimalist footwear and getting athletes I coach into same.

Nothing reinforces improvement in stride mechanics quite as well!

Very nice site; regards!

Anonymous said...

I ran for a short while on neutral, well-cushioned (and quite expensive) shoes. I became injured although nothing changed in my training regimen. Switching back to so-called "stability" shoes that I was well-accustomed to allowed me to continue on with my training and heal from the injury.

What seems like a plausible analysis of the problem is as follows: excessive heel cushioning widens the range of motion at the heel strike. My injury was achilles tendonitis, which is attributable to this kind of motion.

I'm not a big proponent of a "follow the technology" maxim of shoe comfort and running performance, however it would seem that, at least in my case, the only times I have ever been injured in 30 years of running has been when I ran in shoes not well suited to my feet and gait.

jacob said...

Hi Ross,

Thanks for all the great posts. I've found this one particular interesting as I've been running for over 10 years and subscribe to the less is more philosophy in terms of shoe choice. Could it be that all the new motion control technology might be contributing to lazy feet?

If you have weak ankles, wearing supportive braces just makes them weaker without addressing the cause. Isn't this, in essence, what the running shoe industry is doing with all their supposed corrective measures? (posting, motion control gadgets, etc.)

I came across this article comparing barefoot and shod running kinetics and wondered if this addresses the question regarding contact time:

C. Divert et al. Mechanical Comparison of Barefoot and Shod Running. International Journal of Sports Medicine, 2005; 26: 593–598

The results show a decrease in stride length (thus an increase in stride rate), contact time, and flight time for the barefoot protocol while running at around 8 min/mile or 5 min/km pace.

But the really interesting thing is that initial impact forces were reduced as well! It seems a little counterintuitive that cushioned shoes would increase joint moments (as compared to a barefoot condition) so I was hoping you could shed some light on this.

Also, the authors speculate that running barefoot could "enhance the stretch shortening cycle behaviour of the plantar flexor muscles and thus possibly allow a better storage and restitution of elastic energy." Is this in accordance with what you were saying about sprinting spikes (being stiff and rigid for greater energy storage/return?) So a rigid foot could store/return energy better than a cushioned shoe, right? Theoretically then, shouldn't one be able to have better running economy without shoes?


I realize there are a lot of complex variables at play here but I really appreciate your guys' ability to untangle even the most difficult physiological/biomechanical issues.

I'm racing next week (first place wins their weight in beer!) and I'm trying to decide whether it may be worth it to Zola Budd it.

Lem said...

Hi, guys.

I'd like to throw in my own anecdotal evidence on orthotics as a counterpoint to the trend that seems to be forming.

I have been using custom orthotics on neutral-cushioned shoes and it has actually helped me. However, the mechanism is not the control of pronation as the shoe companies suggest. What seems to have happened was that I have somewhat reshaped my foot as the muscles got stronger.

So it goes back to Ross's take that it is training that leads to the positive changes, though in this case it was induced by orthotics. Also, it is worth mentioning that there was hardly any positive effect on my medial arches (although there is some), but there seems to be a big difference in my transverse arch and how force is now distributed at forefoot/fullfoot strike.

I vaguely remember a (validation?) study cited by Noakes in Lore of Running about how pronation is not controlled at all by inserts. (I believe that in this study they put some sort of pins as markers on the heel bone itself!) As for all the positive experiences of people on orthotics, the explanation proposed was that the muscles of the leg were taught to fire more appropiately for the task of running.

Oliver said...

To add to my earlier comment, I think (and have been saying so for the last 4 yrs) that the anti pronation 'horse' is at the stable door already.

After twenty odd years many serious runners are reverting back to neutral shoes. A much maligned 'big shoe company' was said to have lost the plot in running, and stuck with their flagship neutral shoe (think the first one was mid 80's), whilst another company, which used to be a Tiger :) took the market by control with one in three people running in their huge double deckers.
The game is up, and you may be preaching to the converted soon.

BTW, 'much maligned company' has improved its neutral range, still the old flagship, plus some competition versions too, plus specific shoes which address problems such as bunions (my wife adores that one.. first time in her life she runs pain free).

And the tide is turning.

Seriously, if you have motion control issues, biomech etc then start with a 'neutral pallette' and work the adjustmenst in.

Oliver said...

Oh and btw two more things.

Hey Ross, no more personal anecdotes to make a point.. you are slacking off :)

And that Dr Craig guy, remember a shoe designer/producer? could have a vested interest.

Just a scientist looking after the science :)

Ross Tucker and Jonathan Dugas said...

HI Oliver

Thanks for the comments, well put!

I agree 100% that we're moving towards a change in the industry. Interestingly, I had a meeting this morning with one of the other big companies, though it was unrelated to product design (I consult and advise some athletes they sponsor and do the odd presentation on training). The conversation shifted to the shoe market, and I was assured that the anti-pronation market is very much alive and kicking! So perhaps you are part of what a marketer would call the "innovators", the first movers on the trends! Maybe it will require a generation to 'wash out' the preoccuption with the heavy double deckers? To get the horse out of the stable, so to speak, now that it's at the door?!

Thanks for the comments!

Ross

Ross Tucker and Jonathan Dugas said...

Hi again Oliver

Ah, I enjoy being held to high standards by the readers!

In my defence, I will claim that given the topic, I chose to go the "personal" route because shoes are clearly something that affects runners very personally.

It's funny how this topic has evolved - when I did the first post, it was really just a short filler post before a few posts I had been planning on fatigue, and overnight, it drew some really personal responses, not only those you read here! So to then follow up, it was clear that the issue would stimulate a great deal of thought and discussion, so I adopted a more anecdotal approach!

But never fear, I have a few interesting studies up my sleeve for the next post or two, which I'll hopefully do tonight or tomorrow - a look at biomechanical studies on different shoes and barefoot running, so it's back to the books next time round!

Ross

Anonymous said...

Ross,

Hi, I apologize, but I can't seem to locate your email address from our previous conversations (and since I am working at home I dont have my files). I would like to talk to you about a few things for potential articles, my email is brittany.sauser@technologyreview.com, please send me an email when you can, thanks!

Brittany

Anonymous said...

One more personal story: For the past few months I have had trouble with plantar fasciitis. Last Sunday I chose to race in a 15K event using racing flats and although I cannot say my race benefited from their use the next days after the race my calves were sore but my usual heel pain was almost gone. Maybe the less supportive footwear helped me but I have to verify it as I plan to run progressively more kilometers with my minimal shoes.

George

Jae said...

I'm coming a little late to this discussion, but as a Feldenkrais practitioner specilizing in working with runners, I deal with this question all the time.

Because of the importance of proper foot functioning for running, I work with my clients to get them out of orthotics and anti-pronation shoes if they use them, and in five years so far I've never had a runner, regardless of their foot structure, who didn't feel better and run better as a result.

I don't usually need to look at a runner's shoes to know whether they're anti-pronation; all I need to do is close my eyes and listen to their footfalls as they run on pavement. They make a distinctive dead-sounding clunk. Along with this, I always find that they over-work their low back muscles trying to haul around legs that don't have enough spring due to the shoes, and a reduced and slowed range of motion in the legs.

When I find this, I help them learn how to use both arches of each foot, fully use the movement potential in their ankles and, most importantly, make sure they can feel how to move their hips, trunk, and head well enough laterally that they can find support along the outside of the foot rather than just collapsing their arches and falling inward.

Once we've done this, no runner I've ever worked with has needed orthotics or anything but a neutral shoe.

This last bit about the hips, trunk, and head is so important, because in order to use your feet well, you have to use your whole body well. Someone posting earlier mentioned putting aside their orthotics and taking up single-leg squats to warm up for running, and that is a great strategy (and one I use myself when I run) because in order to do a one-legged squat properly you have to move your whole body over your foot so it's properly supported. Cultivating that ability not only helps you strengthen your hip and leg muscles and coordinate yourself to get good support from your feet so you don't overpronate -- it also helps you continually hone a fundamental movement skill for running: moving your weight fully from one leg to the other.


Ross and Jonathan, thanks for making a place to discuss this kind of issue. It's incredibly valuable.

Stan said...

I was just diagnosed with plantar fasciitis. I've always worn a neutral shoe, but I also have neutral orthotics. My orthotics are designed to take the pressure off my right sesamoid, which broke into three pieces. This has cured my sesamoiditis.

So last week, I go in with a recurring case of plantar fasciiitis and my podiatrist raises the heel on my orthotics by a small amount. He said it would make me "more efficient" but we didn't go into the reasons why. He said if I didn't like it I could just peel modification off.

Since there are some experts here, I'm wondering what you think of this. It feels a little less stable now, but I did just run the fastest race of my life after the adjustment. So now I'm torn.

Stan

adventurelisa said...

I agree that anti-pronation shoes are over emphasised. I have long believed that you can train yourself to minimise pronation and to run with a neutral gait. It is all about biomechanics - and the muscle strength and flexibility you mention. You don't need orthotics, wedges or mega-pricey, well-marketed shoes to correct this.

Yes, heavy motion control (MC) shoes are becoming extinct. We see very few of them for our Runner's World shoe reviews (adidas brought out an Adifusion MC shoe in Sept 2007). Anti-pronation (we call them stability) shoes are as numerous as neutral models. Of interest, trail shoes are neutral because your foot needs to roll in all different directions on uneven surfaces so there's no need for off-road shoes to "slow rate of pronation" for a "smooth heel-to-toe transition".

Cheap vs expensive shoes
The current (March 2007) issue of Runner's World SA has a gear section on Shoes Under R700. I was absolutely delighted with the shoes sent to me by the manufacturers. Most were not my size but I squeezed (or spread) my feet into every style to get at least a bit of a feel for them. Nice stuff out there. It is interesting to note that some manufacturers will present a shoe with many technological bells and whistles in a lower price range. To do this they compromise on their profits so that they don't lose a space in the market. Yip, it's true; from the horse's mouth.

I am disappoined that you won't find these inexpensive shoes in specialist running stores, which are attended by staff able to offer new runners good advice on footwear. Running is a convenient sport where little equipment, except for shoes, is required. And a lot of shoes out there can break the bank and turn away any people wanting to give it a bash. I believe in upgrading once you know what you want; but if your R500 shoes work for you, keep with them - no need to upgrade if what you have works.

I've been running in mid-upper range shoes for years and I have a liking for nice cushioning when I'm on the road, especially as I alternate from on-road to off-road all the time.

Recently I had to retire my regular road shoes; they were completely fried and I was feeling a twinge - a sure sign they were gonners. Too much accumulated mileage had snuck up on me (and them). I was waiting for my new fancy ones to arrive so I bought one of the pairs that I'd seen for the Under R700 review, wanting to give them a proper try. I think they cost me R429 or so. The next day I ran the Brooks 32 in Springs.

The shoes were great until 15km when I really started to feel the pounding. No blisters or hot-spots, just too little give and cushioning. Bottomline is that these shoes are great for distances up to 15km; they're not >21km shoes. Even though I felt the impact, I suffered no dire after effect the next day and no biomechanical alterations.

In your blog you mention Clyde's research to see how runners rated cheap vs expensive shoes on the "basis of pressure under the foot and comfort". Indeed, these are subjective. I've just taken a quick look at the abstract but it doesn't mention running pace or distance.

From my recent experience of one pair of low price range shoes from one brand (I usually run in the same brand's medium and high priced shoes) I can comment that over 5km running at 5min/km I would have agreed that the comfort was pretty similar. But after 32km it was certainly a different story. I won't run distance in them again but they are great for step aerobics.

Nonetheless, I don't believe that price is the main factor in deciding comfort. I may have had a more comfortable experience in a similarly priced shoes from a different brand or a different model from the same brand. It all depends on the shoe and your foot and how well the two are matched.

Anonymous said...

I recently observed that after running for a long period of time, the arches of my feet would begin to cramp. Is this a problem of running shoe or running style?

Tebogo said...

You seem to say biomechanics extrems can be dealth with proper training. My foot is high arched and was introduced to orthotics this year because of recurring ankle injury and collaping arch. I however don't want these orthotics, what will be the right training for such situtation?

Philipp said...

Hi Ross and Jonathan,

I am very sympathetic to your claim that it is better training, not more expensive running shoes that is the most likely to avoid injuries.

In that regard, how about a post - or a series of posts - with tips and advice on training? More specifically, what types of training is can help avoid common injuries?

Many thanks, Philipp

Josh said...

The lightest pair of shoes I own are 10 oz (Asic DS Trainer's). I usually run in Asics Kayano's, which weigh 13 oz. What kind of shoe weighs only 6 oz? Do people really run long distances in these? I'm training for a marathon and Half Ironman, so I run in excess of 20k regularly. I'd like to try lighter shoes, but I want to make sure they will feel as comfy as my Asics.

James said...

Hi, that was an interesting article, thanks. Also interesting is the question of weight. My running shoes must be at least twice as heavy as most of my friends! They are all smaller than me, some a lot smaller. The idea that with injuries you should look at training first is so obvious I'm surprised you feel teh need to repeat it. But on the shoe front has anybody looked at the effects of weight on injury/performance?
Cheers
James

julio said...

Que pase a la historia los calzados pesados y también los precios de hoy que a mi parecer son un poco ridiculos.

Julio César Fernández said...

To go down in history and heavy shoes today's prices that I think are a little ridiculous.