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Hi Eric,

You right... especially if the environment will produce too much nociceptive stimulus... and you are not fully adapted. (note that the adaptation is the key factor here to explain that point... some exception -and dogs- can run very fast in very hostile surfaces)
But it's true between "protection" vs "nothing"... so the next question is what kind of protection?
* 11 studies have shown that for each 100g in you feet, you increase your O2 consumption of 0.7 to 1.0%.... HUGE!!! Conclusion: the shoe need to be as light as possible.
* Even if there is not a lot of studies and it's a little controversial, some characteristics of the biomechanics seems more efficient (example of the freely chosen cadence around 170-190 and less vertical displacement) than others. We know that the moderne big bulky shoe have a big impact on some of these factors.. on the wrong way! Conclusion: the shoes must not interfere (too much) with efficient biomechanics but need to protect the foot in function of our adaptation process (less interface, less ramp, more flexibility, ...)

So my questions:
Is the next 10 000m track record (clean surface) can be done by a adapted barefoot runner?
Why people train 80 to 90% of their training volume in big bulky shoes and compete in racing flat shoes?
Blaise

Blaise, thanks for taking the time to attempt to answer my questions. However, you still have not provided me with a good definition of the term you so frequently use: "sensitive/proprioceptive heel strike". [The proper English idiom for what you said is "Don't put words into my mouth".]

I wasn't trying to "put words in your mouth" by saying that since you are now classifying some heel-striking runners as having what you call a "sensitive/proprioceptive heel strike" that the other heel-striking runners must then have a "unsensitive/unproprioceptive heel strike". This is common logic, Blaise. As soon as you start to classify any group of items, whether they be golf balls, running shoes or heel-striking runners, then you must use a proper definition for your classification so others can understand you and not misinterpret your meaning.

For example, if you have 100 golf balls, some of them white and some of them other colors, you could group those 100 golf balls into white golf balls and non-white golf balls to make two groups that I think everyone would understand. However, when you now take a group of runners that is exceptionally large, in other words 80-90% of runners by the most recent studies are heel-strikers, and then declare that only some of them have, what you like to call, a "sensitive/propioceptive heel strike", then since you can't seem to give me a proper definition for what this means, then the other heel-striking runners must logically have a "unsensitive/unproprioceptive heel strike". Wouldn't you agree?

Let's take a step back and look what the definition of proprioception actually is.

So, Blaise, what you are saying are that only a percentage of the millions of runners who choose to heel strike have the ability to unconsciously perceive the movement and spatial orientation of their feet and legs from stimuli originating in the body itself, when you choose to classify only a percentage of the millions of heel-striking runners as having a "propriocetive heel strike". Isn't that correct?

Rather, Blaise, I believe you have chosen to use the term "sensitive/proprioceptive heel strike" (which I believe to be a undefinable term and one that you, or someone else, just made up out of thin air) and have yet to provide a good definition for, to be a classic case of what is called in the science of debate as "moving the goalposts".

Let me explain further. We started out this minimalist shoe/non-heel-striking nonsense a few years with Chris McDougall (who, by the way, calls me the "angry podiatrist") the Chi Method group, the Alexander Running Method group, the Pose Running Method group and a few others saying that heel-striking is bad! and it is better to be a midfoot or forefoot striker, even though we knew by that time that approximately 75- 80% of all runners were heel-strikers (Kerr BA, Beauchamp L et al: Footstrike patterns in distance running. In Nigg BM (Ed.), Biomechanical Aspects of Sport Shoes and Playing Surfaces, University Press, Calgary, 1983, pp. 135-142, Hasegawa H, Yamauchi T, Kraemer WJ: Foot strike patterns of runners at the 15-km point during an elite-level half marathon. J Strength Cond Res, 21:888-893, 2007). These studies were before Pete Larson's recent study that now shows over 89% of runners are heel-strikers (Larson P, Higgins E et al: Foot strike patterns of recreational and sub-elite runners in a long-distance road race. J Sports Sciences, 29:1665-1673, 2011).

Now, these minimalist shoe/non-heel-striking advocates saw a problem with their previous claims that 80-90% of runners were doing something wrong and couldn't come up with a reasonable, logical or scientific explanation of why only some of these heel-striking runners got injured, why some of the world's most elite marathon runners were heel-strikers, why people who heel strike while walking don't often get injured, and why we shouldn't naturally heel-strike when the calcaneus is, by far, the largest and most robust bone in the human foot.

Because these minimalist shoe/non-heel-striking advocates, seeing that there was a real problem with the scientific fact that the vast majority of runners heel-strikers but only a small proportion of those runners get injured and those that are trained to run non-heel striking manner will become less metabolically efficient at running (Dallam GM, Wilber RL et al: Effect of a global alteration of running technique on kinematics and economy. J Sports Sciences, 23:757-764, 2005), they then had to change the standard tune that they were playing in all their lectures on the subject, that all heel-striking running is bad and all midfoot and forefoot striking running is good.

Then along comes someone who now says that it is now really OK to heel-strike, but you must do this heel-striking sensitively and proprioceptively. He says that these runners don't get injured by heel striking because they run with a "sensitive/proprioceptive heel strike". In other words, this individual has chosen to, in the words of debate tactics, to "move the goalposts" and now claim that it is actually OK to heel-strike but as long as these runners do it sensitively and proprioceptively. The evidence for this "moving of the goalposts" in the debate of minimalist shoe/heel-striking debate by this individual is as follows:

1. He can not give a scientific definition for the term "sensitive/propioceptive heel strike" that would allow other scientists to test his hypothesis.

2. He has not a shred of scientific evidence that those heel-striking runners that do get injured are running with less "sensitivity" or less "proprioception" than those heel-striking runners that don't get injured. He is guessing.

3. He can not offer scientifically valid method, either by examining the kinetics, kinematics or by testing neurological function of heel-striking runners by which to discriminate those millions of heel-striking runners into a one group that is "sensitive/proprioceptive" and the other heel-striking runners that must logically be "unsensitive/unproprioceptive". Again, he is guessing.

My conclusion is that this "moving of the goalposts" being seen now with the minimalist shoe/non-heel-striking advocates is just the first step toward them moving away from their dogmatic denial that people run faster and better in shoes, but also to them acknowledging that athletic shoe technology has been one of the prime factors in allowing many people to run pain free on the surfaces we face today in our modern society.

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

Hi Kevin,
Love do discuss about this topics with an advocate of ... (I try to understand what your position and I wonder what your hidden agenda if you have one) hope that is not just a angry podiatrist...

I feel that you have a opinion on the minimalism that are not the same than me (know that I have no problem with that). And if we want discuss about biomechanics and hell striking we need to speak about shoes... the principal reason why 90% of the recreational runners heel strike!!

I think you know what I want to say about sensitive heel strike... (Maybe I will change this definition after our conversation, for "protective heel striking"... referring not just to sensation for protection but protective biomechanics... Like that, I will be able to tell you the degrees of the VLR ramp to give you clear scale of categories. :)

See some part of a discussion with Craig Payne, with who I had a great conversation some month ago.
CP : What's "propriocetive heel strike"?
BD : A light heel strike… to feel the ground… to engage all the impact moderating behaviour and muscle contraction…
To deferentiate to the 45 degres dorsi-flex ankle with the knee in extension that we see often with big bulky shoes…
CP : Is “proprioceptive” the right term to use in this situation? I would have thought that a heel “strike” to initiate that sort of process is actually mediated through exteroceptive pathways and not proprioceptive pathways. ??????
BD : You right! We start to use this term because physio was understand well the 'sensitive' sense of 'proprioceptive' heel strike (in french we use proprioception in the sense of 'perception of our body segment' even if it's not the precise definition… This nomenclature is good for health professionals to explain that not all heel strike are the same in a point of view of efficiency and 'security'… But again : you right… we need to change the term for 'sensitive heel strike…'

Also see some comments about your numerous answers/questions (it's a day off today... I won't be able to take time like that all the time)

... group those 100 golf balls into white golf balls and non-white golf balls to make two groups.
:) love your explanation... now I understand... I'm waiting your categories of heel strikers and will define mine after that...
Some friends of me, podiatrists, are very good on that : pronator or supinator, flat or cavus, varus or valgus ... sorry that's for another post :)

... 75- 80% of all runners were heel-strikers
You forget to named (Nett-1964) ... and to say that in the study of Hasegawa, in the first part of the pack (50 first runners) only 60% was heel striker...
when I listen you message, I fell that for you, there is one and only one category of heel striker. You said no in a other reply but you don't explain... Can you please, to have a better understanding of your actual position.

... millions of runners who choose to heel strike
They didn't' choose! Shoes imposed or promote that kind of biomechanics...

people run faster and better in shoes
You need to explain that
Faster? See my opinion in the post above
Better??? how do you define better biomechanics? heel striking? (I'm a little anxious of your answer)

athletic shoe technology has been one of the prime factors in allowing many people to run pain free
You need to explain that. (your opinion is OK as no good supportive science support that)
My opinion : New technologies promoted annually by shoe companies are not supported by published scientific evidence and are potentially armful (hight heel, interference with perception of the ground contact, rigidity, softness, last not always at the shape of the foot, ...)

... why some of the world's most elite marathon runners were heel-strikers
The majority of the elite runners (the real one ... the front of the pack) have a mid foot strike pattern or a heel strike with a very low foot-ground angle (50-50). FAR from the heel strike that we see with the majority of the recreational runners (Again : is it for you the same category?)... you can named some classic exception like Meb (last year) or Goucher, but they are rare.

... why people who heel strike while walking don't often get injured,
Are you saying that walking is comparable to running? you probably joking...

... calcaneus is, by far, the largest and most robust bone in the human foot.
Again, are you joking? Are you using the "cushion fat pad / strong calcaneus" argument to tell to people to heel strike? just try to jump on your heel versus on your forefoot (one foot hight) and you will realize that some way of landing are a lot more efficient to absorb the shock... it's not because "anatomical structures" (bone and fat pad) but biomechanics...

... trained to run non-heel striking manner will become less metabolically efficient
Also taking position on one specific topics needs to be intellectually honest and citing not just one study to explain what we say. (I have some bad experience about that kind of debate http://www.therunningclinic.ca/blog/...e-on-footwear/ ). I don't wanna say that your are like that... but I thing that we cannot cite "... and those that are trained to run non-heel striking manner will become less metabolically efficient at running (Dallam-2005)" if you don't cite the study of Fletcher-2008 "... No significant changes pre-post test, were found for an economy run... but a lot better time trial even if not significative"... and we cannot speak about a specific subject like heel strike pattern and using article using 10 others biomechanical points to say "... and those that are trained to run non-heel striking manner will become less metabolically efficient"
And I don't say that people need to run Pose or absolutely run forefoot. (many explanations in previous post about my position)

...citing blaise : OK to heel-strike, but you must do this heel-striking sensitively
YES : ok to heel strike if you have in the same time, good impact moderating behaviours... and your heel striking don't increase the VLR to much... and for that, you need to feel more with your foot OR learn to do it OR to be the lucky person that do it unconsciously (like some barefoot runner former -young age- that crystallized efficient and safe biomechanics... and continued to run like that with big bulky shoes (exception only or people running a lot).

... The evidence for this "moving of the goalposts" in the debate of minimalist shoe/heel-striking
It's pretty close one to the other... difficult to separate both debate... and it's a lot more trendy :)

... debate by this individual
that's me... Blaise Dubois :)

... ...

Kevin, I thought that I answered to your question of what is a sensitive heel strike. You do not seem to accept my unscientific definition. So I will try to do it better after you clearly answered the principal question of this posts : Is all heel strikers are the same (point of view of efficiency and injuries)... with explanations please

Blaise

Blaise,

By the way, Blaise, I think you are a pretty cool dude...that is Californian for saying that I like you and the manner in which you are answering my questions.

There is no hidden agenda on my part. I'm just a health professional that becomes concerned when certain people start advocating that everyone should be running in shoes that are built like racing flats, should be running more on their forefoot than their rearfoot and are getting injured as a result. I'm just trying to protect the running public from the nonsense with minimalist shoes that is going on currently and that is causing many runners to get injuries they never would have had if they had not listened to the "experts on minimalist running shoes" and just continued training in their previous, more conventional running shoes.

http://birthdayshoes.com/keith-olber...in-fivefingers

http://www.boston.com/lifestyle/heal...9/youre_crazy/

http://www.podiatry-arena.com/podiat...ad.php?t=48566

Do you have any evidence that conventional running shoes are bad and that heel striking is bad? I don't know of any. If heel striking it so bad then why don't more runners run with a midfoot/forefoot striking pattern? I believe that 80+% of slower runners choose to heel strike because not only is this is the most comfortable way for them to run but also it is the most metabolically efficient way for them to run. I know, Blaise, you will then say that they only do that because they are running in "big, bulky shoes" which seems to be a favorite phrase of yours.

In that regard, do you have a definition for what a "big,bulky shoe" is? Maybe you can give me some cutoff values for grams of mass, rearfoot and forefoot sole thickness, heel height differential and any other parameters as to what allows one size 10 (US) men's shoe to be classified by you as "big and bulky" and another shoe to be classified by you as being "not be big and bulky". I hear minimalist shoe fans throw around this term "big and bulky" as a negative way to describe traditional training shoe designs but, when I pin them down and ask them to define "big and bulky", they seem to not be able to tell me exactly which shoe design elements make them "big and bulky" and which shoe design elements make them "not big and bulky". I hope you are different in this regard. Here is another chance for you to come up with a proper definition for the phrases that you seem to throw around in many of your conversations on running biomechanics and running shoe design.

I agree that you should eliminate the term "sensitive or proprioceptive heel strike" since you have absolutely no idea whether some runners have better proprioception or better sensitivity than other runners....you are just plain guessing...and this isn't good science. In addition, I don't think that "protective biomechanics" is any better for the same reason...you would be guessing and this also isn't good science.

Rather, why not separate out heel-striking into two categories? (and I have even defined them for you):

1. Injury prone heel-strikers: Heel-striking runners who get injured frequently (more than one injury per year that prevents them from running for at least 7 days in a row).

2. Non-injury prone heel-strikers:Heel-striking runners who don't get injured frequently (less than one injury per year that prevents them from running for at least 7 days in a row).

That classification system is certainly much better than your "sensitive/propioceptive heel-strikers" and "unsensitve/unproprioceptive heel-strikers" since it can easily be scientifically studied, has a clear and unambiguous definition, and research on these two categories will actually be helpful for those of us who treat group #1 of these runners on a daily basis.

Alternatively, you could classify heel-striking runners in regards to their kinetics (e.g. vertical loading rate), in regards to their kinematics (e.g. angle of shoe sole to ground at instant of initial ground contact at footstrike) or even in regard to their proprioceptive neurological function (e.g. ability to discriminate ankle rotational position correctly when blinded). Please, please, Blaise, discontinue this talk of "proprioception and sensitivity" when you refer to heel-strikers because it makes it look like you are "moving the goalposts" as I mentioned in my last post.

I appreciate the fact that English is not your first language but you are doing a great job at communicating what, I think, you mean. In addition, I appreciate your honesty and your willingness to debate these topics with us since you seem to be very knowledgeable regarding the available research on these subjects. It is good to have you here on Podiatry Arena. I'm greatly enjoying discussing these fascinating subjects with you.

Like I said in a previous post, I started my competetive long distance running career at the age of 13 (I am now 54) and ran competetively for about 30 years. In addition, I have been treating runners and their injuries for the past 27 years as a sports podiatrist. Over the last 27 years of treating runners, I have paid close attention to the stride length of runners and advise them to not overstride, to increase their stride frequency, in the hopes that this will lessen their injury risk. I have not told them to heel strike, midfoot strike or to forefoot strike but rather have told them to listen to their body when they run to select the best footstrike pattern for their own body. In addition, I will often try to have them shorten their stride length to lessen impact force.

Therefore, what you are doing, Blaise, is very close to what I have been doing for the past quarter century with my runner-patients. However, I also pay close attention to many other factors, too numerous to count here. I am, however, attaching an article I wrote when I was 25 years old that discusses the questions that a clinician may ask during a proper runner-patient history that will better explain all the factors I look at when I treat runners. In other words, I don't just look at foot strike pattern when I treat injured runners like many of the minimalist shoe advocates that seem to think that this one small factor is the most important thing that causes running injuries and affects running performance. I think you might find the paper interesting and I hope it gives you a better idea of where I am coming from as a runner and as a sports podiatrist.

Attached Files

Runner-Patient History - What To Ask and Why.pdf (528.4 KB, 14 views)

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

That is debatable. The oxygen consumption study was done by adding weight to the leg of shod runners. They wore shoes with and without the added weight. We don't know the additional energy cost of running barefoot. You have said, and I would agree that runners have to adapt to running barefoot. Perhaps gthe adaptation uses more energy than carrying the extra weight of the shoes. Some of the adaptations that have been mentioned are forefoot or midfoot striking. One mechanism that the body has to absorb the impact at contact is to use the gastroc soleus muscles to slow dorfsiflexion of he ankle after a forefoot strike. Perhaps this uses more energy than the anterior tibial lowering the forefoot to the ground after a heel strike. Another adaptation to barefoot running may be increased knee flexion. This has also been shown to increase metabolic cost.



My experience with barefoot running consists of one beach vacation where I forgot to bring my running shoes. For three consecutive days I ran along the beach and I consciously looked for the sand with the right density where it allowed me to heel strike comfortably. That's what felt the best. Now if you could tune he track so that it had the consistency of the perfect hardness of semi wet sand, you might see.... Then again, they might lose speed at the push off.

Maybe people train in "big bulky" running shoes because they feel like they are more likely to get injured if they run in minimalist shoes. When I ran in my Nike aqua socks, it was not very comfortable.

Eric

How true .... the trend to minimalist/barefoot is a major economic stimulus package for all who treat running injuries!

What should we do when we see all these new injuries coming in the door? Rub our hands together and keep quiet and keep the $ or speak out and warn people of the dangers.

My issues has always been: Its the use of cherry picking and confirmation biases. Its the use of cross-sectional studies to imply causation; its the inappropriate extrapolation of lab based studies to clinical outcomes; its a critical appraisal of research that does not support an agenda, but the lack of that same level of critical appraisal of research that supports an agenda....

I would not draw that conclusion from that data. If minimalist/barefoot running is supposed to strengthen muscles, then why are they getting stronger? Surely it must be because the muscles are working harder --> greater metabolic cost of running minimalist/barefoot

Also, running shoes are very light these days anyway. Some of the earlier studies with running shoes were done when shoes weighed a lot more that they do today.

Surely, at the elite level they need a shoe as light as possible, but still has design features that reduce muscle activity to it minimum, so they got more for running fast ... its Niggs's tuning paradigm....it going to be trading off one for the other and that trade off will probably be different for each runner.

__________________
Craig Payne
__________________________________________________ ___________________________________
Follow me on Twitter | Run Junkie | Latest Blog Post: Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe
God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.

Don't forget the data in this previous thread:
Impact frequency data suggest unique risks for forefoot strikers

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I will give you my secret (how I move more that 1000 patients in flat shoes in the last 10 years without injuries) to do a "smart and scientific minimalist approach"... around a beer... pretty sure we will meet each other on days

Again there is a continuum between barefoot and the Hoka (263 definite categories). For me the cutoff is all light trainers and bigger. You have big bulky shoes (ex: DS trainer or Nimbus), you have also the SUPER big bulky shoes (ex: beast) and the SUPER-EXTRA big bulky shoes (Hoka).

More you are far to the barefoot condition more is a big bulky shoes. I don't say that everybody need to run barefoot, but I'm convince that most of technologies are useless and possibly armful. The move to buy a new pair of lower, thiner, more flexible, more light, ... is depending of the patient capacity for adaptation. (and other criteria)

I recommend big bulky shoes for three reasons (together) :
1. use to run with that kind of shoes,
2. not injured,
3. don't want perform.

Sorry Kevin you don't convince me,
the goal is to discriminate people that I think are "more prone to be injured" and not "who are injured". Because I think that running with a huge VLR associate to very low impact moderating behaviour and 45 degrees dorsi-flex angle at the contact time is more dangerous than a "sensitive heel stike"

Good idea... and we will realize that there is a link between: VLR / Foot Angle / Rampe and thickness of the shoe... and the capacity of the foot to feel the impact force... and we will call this a "sensitive heel strike"

Thanks a lot for the article, I will read it with a lot of attention
see you one time
Blaise

Hi Eric,
Sorry but it's not! Do you have one single study showing the opposite?
(2011-Hanson, 2008-Divert, 2009-Bonacci, 1985-Burkett, Squadrone 2009, 1994-Flaherty , Catlin 1979, Rlston 1981, Soule 1969)

NO. many study about barefoot vs shod. See a interesting theses about that, from Divert, a french scientists, adding weight to the upper part of socks vs shoes to know what the mass effect vs "lost of energy in the cushion" effect (2008-Divert)

Yes we have an idea... even in shod population: increase by 5,7% the O2 consumption in regular modern shoes vs barefoot (2011-Hanson)

Difference in biomechanics (barefoot vs shoes) doesn't change significantly the production of CK (indicator of muscle works)

95% of the recreational runners have no choice... they can buy just that kind of shoes and everybody are recommended those kind of shoes... Let them choosing by the comfort and they prefer light trainer over motion control shoes (2010-Kong)

Blaise:

How do you know that 95% of recreational runners "have no choice" in the shoes they buy? Do the shoe salesman force them to only buy one type of shoe? Do you have a reference that supports this conjecture of yours? You must be joking?!

Also, how do you get this opinion that runners "prefers light trainers over motion control shoes" out of the 2010 study by Kong et al where they were studying the kinetic and kinematic effects caused by shoe degradation???

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

I'm sure you are joking

100% agree!!! Love your quote...

Every clinician practices within his own knowledge. This knowledge is constantly brought to the next level by continuing education, which is unfortunately frequently influenced by promoters who have commercial or philosophical interests. Therefore, we are looking to be oriented towards best practice by rigorous and unbiased science that could be clinically applicable. New clinical guidelines are frequently produced, and a knowledge transfer process is used to spread new information among practitioners. These guidelines bring clinicians to realize how aberrant are certain aspects of their practice, and lead them to change these concepts that maybe were present for a long time… a laborious and sometimes painful process that requires humility!

I personally think that we should elaborate evidence-based clinical guidelines to change our aberrant practices relative to the promotion and the prescription of running shoes. I completely change my practice 10 years ago after some reflexions... based on available scientific literature... it was painful: not my feet... my ego.

Kevin,
95% because there is juste that kind of shoes in the shoe shop!!! Do you know a shoe salesman that propose a racing flat shoes in the choice of shoes he propose to his client... if the client doesn't ask specifically this kind of shoes? And if he asks, he will be discouraged to buy it... it's for tiny fast runners only
(I'm happy to know that it's a little better since 2 years with the trend of minimalist shoes)

Kong wrote many articles in 2010!

Shoe preference based on subjective comfort for walking and running
Kong P.W. and Bagdon M.
Journal of the American Podiatric Medical Association 2010 100:6 (456-462)
Background: Subjective comfort of footwear is important for shoe and orthosis design. This study compared shoe preferences between walking and running, using subjective comfort as an outcome tool. Methods: Forty-one participants walked and ran 20 times each along a runway in three types of footwear (cushioning, lightweight, and stability) and chose the model that they preferred most for walking and running separately based on subjective comfort. Results: More participants preferred the cushioning model ( walking, 34%; running, 41%) or the lightweight model ( walking, 44%; running, 41%) over the stability model ( walking, 22%; running, 17%). x2 tests revealed no differences between walking and running, runners and nonrunners, and lighter and heavier individuals. Women were more likely (odds ratio = 4.09) to prefer the lightweight model, whereas men preferred the cushioning (odds ratio = 2.05) and stability (odds ratio = 3.19) models. Most participants (71%) chose the same model for both activities. Conclusions: Shoe preference varies among individuals and is influenced by sex. Most people feel comfortable walking and running in the same shoe model.

I hope that a shoe salesman does not try to sell a beginning runner a racing flat to train in on concrete or asphalt! Just because you think this is best, Blaise, doesn't mean that it is best...unless you have some good scientific evidence of such and something more than just your anecdotal experience of putting 1,000 runners into racing flats in Montreal with "excellent results".

I have put 10,000 runners into thicker soled training shoes over the past 26 years here in Sacramento with excellent results so my anecdotal experience beats yours by a factor of 10X. ;-)

Seriously, though, I think that the majority of runners still self-select to run in more thicker soled running shoes because thicker soled running shoes are simply more comfortable to run in, especially on asphalt and concrete where many runners choose to run. I ran in plenty of thin soled shoes when I was running 70-100 miles per week and these shoes were only comfortable to run in on grass or when racing to reduce shoe mass. The best shoes for me and nearly every other high-caliber collegiate runner to train in were thicker soled shoes, not the minimalist racing flats that you think everyone should be running all their miles in. I wonder why some of the best ultra distance runners in the world choose the Hoka One One shoe to run their events in...a shoe which you call "Super Extra Bulky Shoes". You know, Blaise, Hoka One One shoes were designed by some French trail runners.

http://www.youtube.com/watch?v=vrAF6ZrI1v0

And, I don't even know why, Blaise, that you get so excited about reducing impact shock. There is no conclusive evidence that impact shock is the cause of even a minority of running injuries.

Here is what the world's best scientific researcher on running biomechanics, Benno Nigg, says about impact shock and it's relation to running injuries in his latest book.

Maybe once you have sufficient data, Blaise, to actually support your conjecture that impact shock is a major cause of running injuries, and you then also have sufficient data to support your conjecture that running in thin soled shoes reduces injuries and doesn't cause other types of injuries, then I will be more impressed with your opinions. Until then, I am having a great time "chewing the cud" with you and hope you stick around for more fun. I'm just getting interested.

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

Blaise:

It would probably not be good for you, since you seem to want to be scientific, to start delving into the "mystical arts" to come up with a term such as "sensitive heel strike" to describe one type of footstrike versus another.

How exactly are you determining that one footstrike is more "sensitive" than another footstrike? Or, as I suspect, you just guessing that this is the case and have not a shred of scientific evidence that the people who heel strike a certain way have any more "sensitivity", whatever that is, than the people who heel strike another way.

It is rather funny, Blaise, that you quote scientific studies in your writings extensively, but, you come up with these mystical, non-scientific terms such as "proprioceptive" and "sensitive" to try to categorize one type of heel-striking runner versus another type of heel-striking runner when you have absolutely no research basis, no data and just pure conjecture to come up with these useless, unscientific terms to describe heel-striking runners.

I'll ask you once again, Blaise...can you come up with an good definition for what a "sensitive heel striker" actually is? How do you scientifically measure this sensitivity? Or do you just pull these terms out of your hat, with no valid scientific meaning to back up these terms?

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
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Yes, I do. Give me one logical piece of science or clinics that justify the prescription of the big bulky shoes for a beginner. You need to prove that, more than me... you do a bigger intervention (its like giving pills for a specific pathology... more the intervention is far from "nothing/habit/nature"... and more it's invasive or have the potential to change the homeostasis... more you need to explain and to justify!!!)

So that's for a new post
1. If someone starts a running program, which kind of shoe would you recommend to this person?
2. What type do you recommend to children and teenagers who run?
4. Do the BBS (light trainer or bigger... 90% of the market) prevent from injuries?

Which years?, not sure it was the same kind of shoes that now...

The best run in more flat shoes that even big bulky shoes (Kuprika, Jornet, ...)

I told in a recent post that the science is not so stong in that topic and explain one essential concept of ADAPTATION (even to big impact force).
But the subject is still debatable (Ask Davis, Powers, Ferber, Hamill, ...) ... and vertical loading rate is certainly better to look that peak pressure (one of the best argument of Simon Bartold to justify is BBS)

I agree that Nigg is the more prolific author in the world about shoes and is book is amassing. So you are agree also that orthotics don't change biomechanics?

For the last 26+ years, I have based my running shoe recommendation for runners on many factors including running experience, running speed, amount of subtalar joint pronation during running, history of types of injuries, body mass of individual, and types of terrain they typically train on. My goal is to put the runner in as light of a shoe as possible that will allow them to run injury free and be comfortable on the surfaces they train on since I have long known that increased running shoe mass decreases metabolic efficiency.

[By the way, Mike Catlin and Rudy Dressendorfer, PhD, were friends and running buddies of mine when I was an undergraduate Animal Physiology major at UC Davis from 1975-1979 where I ran on the UC Davis Aggie Cross Country and Track teams for four years and worked in the Human Performance Lab (Catlin MJ, Dressendorfer RH: Effect of shoe weight on the energy cost of running. Medicine and Science in Sports. 11: 80, 1979). I often ran with Mike Catlin before he won the Western States 100 Mile run in 1979 and 1980, in thick soled conventional running shoes....not racing flats!]

Of course, children and teenagers, due to their lower mass do not need as much of a shoe as do heavier adult runners. I try to tune the running shoe midsole to allow the runner to get some shock absorption from the shoe but also not allowing the shoe to cause excessive subtalar joint pronation.

My past experience both as a competetive runner and seeing thousands upon thousands of runners over the past 26+ years has shown me quite conclusively that the properly selected conventional running shoe is a very safe shoe to run in and is much more safe to run for the vast majority of adult runners than a thin-soled racing flat on asphalt and concrete especially. For trail runners, a thinner midsole running shoe is better to decrease the lever arm for inversion ankle sprains and since the trail surface itself can offer some natural cushioning to the runner, without the shoe having to provide so much cushioning.

So Blaise, it comes down to your anecdotes that thin shoes are better always, versus my anecdotes that a variety of running shoe midsole designs can be used depending on many factors. I just can't see that the research evidence justifies the claims you are making.

However, I do appreciate that you know the research, even though you do have a major fault in making up mystical terms such as "proprioceptive heel strike" and "sensitive heel strike" which have not a shred of scientific research to justify their continued use. Why not move, Blaise, from the mystical arts world and into the world of science when you are trying to describe why 80-90% of the millions of runners in the world willingly and enjoyably choose to heel strike when they run?? Certainly you aren't saying that you are right and these millions of people are wrong in choosing to heel strike when they run....are you??

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

See you around a beer to speak more about all of this
Happy holidays
Blaise

Merry Christmas, Blaise.

Y'all come back now, ya hear?!

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

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Having read Benno's new book, and most of his published articles, I'm pretty certain he has never made the above comment.

I've been enjoying following the discussion on this thread.

Ian:

Benno Nigg never made the comment that Blaise said he did. In fact, when I lectured with Benno at the University of Calgary in February of 2000, he told me in a conversation that if he didn't wear an orthotic inside his shoes, his knees would hurt with prolonged standing so he knew they had to be doing something.

Here is what Benno and coauthors did say about custom foot orthoses:

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
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My location

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was going to post the same thing and went to the paper Kevin posted up below - patients and end of year stuff got in the way and was going to add a comment.


If Blaise is worried about vertical loading rate and taking off the shoes reduces this then so do some orthotics according to Nigg

Have a nice Christmas all

__________________
Mike Weber.



Crazy Mary

The best is to ask to Nigg and read his book again...
Many times he said

My opinion: Exception of the inverted orthotics, the biomechanical changes brought upon by corrective plantar orthoses are slight and non-systematic, sometimes opposite to the expected results.

Interesting lecture on the biomechanical effect of orthotics: Chen-2010, 2009(RS)-Murley, 2008(RS)McMillan, Mundermann-2006, Reilly-2006, Ferber-2005, Kulig-2005, Hertel-2005, Stackhouse-2004, Nawoczenski-2004 et 1999, Laughton-2003, Williams III-2003, Nester-2003, Nigg-2003, 2001 et 1999, Razeghi-2000, Neptune-2000, Reinschmidt-2000, Stacoff-2000 et 2001, Brown-1995

And for sure Effect of foot orthoses on lower extremity kinetics during running:
a systematic literature review (Andrew McMillan and Craig Payne)
- we can analyze it together with Craig-

Eff€ects of foot orthoses on skeletal motion during running (A. Stacoff€ a,e,*, C. Reinschmidt a,c, B.M. Nigg a, A.J. van den Bogert a,d, A. Lundberg b, J. Denoth e, E. Stussi e)

Abstract
Objective. To quantify the e€ects of medial foot orthoses on skeletal movements of the calcaneus and tibia during the stance phase in running.
Design. Kinematic e€ects of medial foot orthoses (anterior, posterior, no support) were tested using skeletal (and shoe) markers at the calcaneus and tibia.
Background. Previous studies using shoe and skin markers concluded that medially placed orthoses control/reduce foot eversion and tibial rotation. However, it is currently unknown if such orthoses also a€act skeletal motion at the lower extremities.
Methods. Intracortical Hofman pins with re¯ective marker triads were inserted under standard local anesthetic into the calcaneus and tibia of ®ve healthy male subjects. The three-dimensional tibiocalcaneal rotations were determined using a joint coordinate system approach. Eversion (skeletal and shoe) and tibial rotation were calculated to study the foot orthoses e€ffects.
Results. Orthotic eff€ects on eversion and tibial rotations were found to be small and unsystematic over all subjects. Di€ferences between the subjects were signifcantly larger (p< 0.01; up to 10°) than between the orthotic conditions (1±4°). Signi®can't orthotic e€ffects across subjects were found only for total internal tibial rotation; p<0.05).
Conclusions. This in vivo study showed that medially placed foot orthoses did not change tibiocalcaneal movement patterns substantially during the stance phase of running.

I think it come back to the definition of Biomechancis - just because bones do or do not move does not mean the device is not changing the Mechanics of the body

__________________
Mike Weber.



Crazy Mary

Blaise:

You might want to check out what these authors call "foot orthoses". Most podiatrists wouldn't call the medial arch pads these authors used in their study "foot orthoses". Would you??

Glad to see you couldn't stay away from all of us too long.

Attached Images

Stacoff orthosis study.jpg (30.6 KB, 55 views)

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

Blaise:

Even, Irene Davis, who also advocates barefoot running and runs barefoot herself, has stated in her previous publications that foot orthoses can positively change the biomechanics of the foot and lower extremity. But how do you wear orthotics if you are barefoot?

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************

Confirmation bias's and cherry picking at its best! There are a lot of studies missing from that list. ~50% of the published studies show kinematic changes and the other 50% do not show systematic changes.

- the "foot orthotics" used in most of those studies bear no resemblance to what people use in clinical practice as foot orthotics
- in the vast majority of those studies we have absolutely no idea if the subjects used even needed a foot orthotic or what foot type they had
- they are lab based studies... what do they have to do with clinical outcomes?

__________________
Craig Payne
__________________________________________________ ___________________________________
Follow me on Twitter | Run Junkie | Latest Blog Post: Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe
God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.

It is very interesting that Irene Davis and coworkers found that subjects that were instructed to forefoot strike had greater tibial accelerations than when they were rearfoot strikers? And I thought, Blaise, that running on your forefoot was supposed to reduce "shock"?! Very interesting!

Also, why, when Dan Lieberman speaks of heel striking running, he only speaks of "collisions" whereas he never speaks of the forefoot strikers as having "collisions" with the ground? Does this notice at the bottom of his webpage have anything to do with it?:

Attached Files

Effect of Strike Pattern and Orthotic Intervention on Tibial Shock During Running.pdf (152.4 KB, 4 views)

__________________
Sincerely,

Kevin

**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College

e-mail: kevinakirby@comcast.net

Private Practice:
107 Scripps Drive, Suite 200
Sacramento, CA 95825 USA
My location

Voice: (916) 925-8111 Fax: (916) 925-8136
**************************************************