Welcome to the Podiatry Arena forums

You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members, upload content, view attachments, receive a weekly email update of new discussions, access other special features. Registered users do not get displayed the advertisements in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!

  1. Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
    Dismiss Notice
Dismiss Notice
Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
Dismiss Notice
Have you liked us on Facebook to get our updates? Please do. Click here for our Facebook page.
Dismiss Notice
Do you get the weekly newsletter that Podiatry Arena sends out to update everybody? If not, click here to organise this.

Optimal amount of pronation finally declared

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Griff, Jul 2, 2009.

  1. Griff

    Griff Moderator


    Members do not see these Ads. Sign Up.
    It seems those chaps at Asics have done it again - they've somehow found that there is an optimal degree of pronation (15 degrees incase you were wondering)

    See this linky

    Does a huge reputable running shoe company perpetuating this sh!te make anyone else cry into their cornflakes or is it just me... sigh...

    Ian
     
  2. footdoctor

    footdoctor Active Member

    Oh really, 15 degrees of pronation is optimum, who on earth came up with that absolute classic!!

    Is 15 degrees of calcaneal eversion not pretty much full end range of eversion excursion anyhow (on average)?

    So an overpronator is someone who pronates more than 15 degrees ( haven't seen many of those) and a shoe alone is going to correct this malalignment?

    Where did the author get his facts from, would make for interesting reading, Ian dont go ruining your cornflakes, its not worth it!!
     
  3. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    15 degrees may be normal from the inverted position at contact to maximum eversion. I know from the Williams & Mclay et al study on inverted vs standard orthoses vs no orthoses, that the mean eversion excursion of all 3 groups was 15 or so degrees, so I guess that is what they referring to.

    The amount would be much less if measured as the amount of eversion past vertical. The ASICS article should have made it clearer

    Anyone who has been to a Boot Camp knows my views and thought processes on STJ range of motion. For straight ahead walking on a hard surface, we probably only need 4 degrees of eversion and no inversion...but if we want to turn a corner, we going to need more. ...if you going to play tennis, you going to need a huge amount more.

    I have seen a slow motion video of a high jump foot plant and take off and the STJ/rearfoot complex everted (pronated), something like 50-60 degrees.

    What is the normal range? There isn't one becasue it activity dependent.

    Having said that, someone at ASICS need to be put before a firing squad as that article promotes the Wet Test for foot pronation. (Simon ... were are you?)
     
    Last edited: Jul 6, 2009
  4. Sammo

    Sammo Active Member

    ?????????

    Thats a pronating foot that doesn't pronate right?

    And what is mild over pronation??

    nnnngggghhhh
     
  5. BwaaaaaaaAaaaaaahhhhhhhhh

    15 degrees from where exactly!?

    We see again the rift between modernist and post modernist biomechanics!

    Depressing init.

    Robert
     
  6. CraigT

    CraigT Well-Known Member

    Craig
    I believe I have seen the same footage and I actually dispute this... The shoe does dramatically distort, but I thik it is the foot shifting medially against the heel counter that does this rather than subtalar pronation. If you can find the footage and post it we can judge...
    Cheers
    Craig T
     
  7. Griff

    Griff Moderator

    I'm with you on this one Craig. I recently wrote some bits for a trainer website and they included the wet foot test and put my name to it. To say I was upset was an understatement... still trying to get it changed

    Yep I wouldnt mind seeing this if anyone has it. Just did a crude you tube search and got nowt

    Ian
     
  8. CraigT

    CraigT Well-Known Member

  9. Griff

    Griff Moderator

    Here you go:



    Discuss...
     
    Last edited by a moderator: Sep 22, 2016
  10. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    You probably right. BUT, the point I was making is that there is NO normal range... the range is activity dependent.
     
  11. Activity and subject dependent:

    Subtalar joint motion = a function of (genotype + environment) + (genotype x environment) + measurement error.

    As for the video, there is obviously deformation of the shoe, but there is also probably more subtalar joint pronation than is commonly cited as the "end of range" ;) It would be nice to see a barefoot one. Moreover, given the "equation above, it seems likely given the biomechanics of high jump individuals who perform this frequently should have different "range of motion" in their take off versus non take off foot.

    Please also note that the subtalar joint axial orientation is constantly changing throughout motion, therefore the planal dominance is also changing. The degree of subtalar joint pronation does not = the degree of calcaneal eversion, so the measurement frame is important.
     
  12. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    Not normally being one to boast about the size of his tools, but I just got myself a new digital video (casio exilim) that can record at 1500 frame/sec (all current video cameras are 25 frames/sec)....all I gotto do now is find myself a high jumper!
     
  13. I was a county standard high jumper in my youth, unfortunately as I now have a ruptured ACL, partially ruptured PCL, torn lateral meniscus and severe bone oedema in my right knee, I won't be able to help- doh. Rugby- it's not big and it's not clever.
     
  14. toomoon

    toomoon Well-Known Member

    Well Craig,
    actually i am in Africa for ISB right now, so I only just got to read this wonderful diatribe.
    You know... this is the kinda crap that just leaves me in despair. It has come out of the UK, and is posted on the ASICS UK website... God knows who the hell wrote it (although I have my suspicions), and where they got their information from, but it is a huge embarrasment to me.
    I just need to do a little resaerch from here and find out who to yell at....
     
  15. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    See you Friday in Stellenbosch :drinks
     
  16. Simon:

    Good to see that Asics is the first running shoe company to have figured out the magic number for the correct amount of pronation lies at 15 degrees.:bash:

    I think that Asics should have picked a number like 14.75 degrees, and then they would really have sounded like they had the data to back that claim up.:cool:

    Oh well, only one of the joys for working for such a huge corporation.....

    Hope you and Craig and Bart all have fun in South Africa. Couldn't make it since I still need to see patients to make a living...... but a little bit of me will be there in Bart's lecture.
     
  17. efuller

    efuller MVP

    Bart van Gheul showed a high speed video of a high jumper at one of the John Weed conferences. At the time he said he couldn't find a high jumper who would be willing to do it bare foot.

    Cheers,

    Eric
     
  18. Griff

    Griff Moderator

    Seems that Runners World concur that 15 degrees is 'normal'

     
    Last edited by a moderator: Sep 22, 2016
  19. CraigT

    CraigT Well-Known Member

    I am pretty sure that the footage above is Bart's- not sure if he posted it or not...
     
  20. In regards to this "normal pronation is 15 degrees" idea that seems to be gaining ground on the internet, it looks like it's time for........The Myth Busters!!!
     

    Attached Files:

  21. rmazoyer

    rmazoyer Welcome New Poster

    Hi all,

    As you may have noticed we (ASICS) pulled the article from the sites this morning.

    Thanks a lot for pointing out this problem, and we're working hard internally to reformulate our explanation in a correct way. As some of you pointed out, we didn't mean "optimal" as a norm, but more as a median measure, that helps people understand the issue. In our enthusiasm to simplify, we've obviously gone over to stating erroneous things.

    We'll be back with a better article, including improved illustrations, in a few days.

    Best regards,

    Raphaël Mazoyer, Digital Communications Manager, ASICS Europe
     
  22. Raphael:

    Thanks for removing that piece of misinformation from your company's website. This will help keep Asics as one of the most respected athletic/running shoe companies within the international podiatry community.

    However, one word of advice is in order. The next time Asics decides to post something as obviously uncertain and incorrect as the "optimal amount of pronation" on a public website, you may want to consider having the website pre-approved by someone with great knowledge in these matters, such as Simon Bartold, rather than causing a potentially embarrassing situation for Asics with gross misinformation being displayed for all to see.
     
  23. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    Raphaël - the information on the wet footprint test is still there. You not doing ASICS any favours having it there, not to mention Simon pulling his hair out (he might end up like me :craig: ).

    In case, you have not seen it, here is the evidence on just how bogus that test is. Interestingly, in that thread, Simon said:
    I guess he must not have been talking avout ASICS
     
  24. rmazoyer

    rmazoyer Welcome New Poster

    Hey Kevin,

    Advice well taken, and while we've been pushing hard to convey our position in a stronger way, we haven't yet worked out all the elements of the process. This is all fairly new for us -- this knowledge floats around the company, with many incredibly knowledgeable people working around the development of products, but actually coming out and clearly stating our position is quite a challenge.

    Basically, we're trying to fill a gap between supply-side information ("we developed this technology because...") and individual specialized information (podiatrists or other specialists in this field giving personal advice based on observation), with the intention to thoroughly inform consumers. Clearly, we must do so without losing any of the rigor and accuracy of our research.

    Again, thanks a bunch for your critical eye, I'm grateful for the high expectations you have of ASICS!

    -Raphaël
     
  25. Raphael:

    This is also the "thin ice" that we clinicians tread when we write articles or give lectures to the lay public. We also find it necessary to sometimes "dumb down" the message to the public, by using less precise terminology, to describe the very complex three-dimensional kinetics and kinematics of the human foot and lower extremity during weightbearing activities. We need to do this in order to provide a basic message that is informational, but also not inaccurate, to the public.

    For example, in the case of describing pronation motion of the foot, a more accurate way of approaching this subject for a public website of a major athletic shoe manufacturer would be to avoid any discrete numerical values that describe optimum magnitudes of pronation motion. Rather, the website should state that pronation of the foot is a normal motion that is required in both walking and running activities, with more motion normally being necessary during running than walking. Excessive pronation can lead to specific types of foot and lower extremity injury, but in each individual, the amount of pronation that produces injury varies from one person to another. In addition, a foot that pronates too little during activities may also suffer from injury with, again, the type of injury depending on the specific mechanical characteristics of the individual's musculoskeletal system. In order for the individual to find the best running or athletic shoe, they need to look for a shoe that will provide the optimal level of pronation, neither too much, nor too little, that will allow them to participate fully in their activity or sport with the greatest mechanical efficiency and with the least chance of injury.

    The above statement could be put into any of the public websites of the major shoe manufacturers with minimal complaints from the international podiatric medical community. In addition, it would provide the public with a much better understanding of the basic mechanics of foot pronation, as we currently understand it, so that this knowledge may be used to positively affect the shoe selection of the purchasing public for their particular sports activity.

    Hope this helps.
     
    Last edited: Jul 7, 2009
  26. Griff

    Griff Moderator

    Hi Raphaël,

    Many thanks for your input here. Its great to see ASICS representatives reading this forum, and responding positively to what we mull over. Really pleased the page has been pulled from the site, as if runners continue to read old and dated terminology and erroneous facts it makes our jobs much harder. Looking forward to the new version. As Kevin says, when you have someone of Simon Bartolds calibre on board it would be criminal not to take advantage of that.

    All the best

    Ian
     
  27. KBruce

    KBruce Member



    I m pretty sure they also use the 'wet test' on their reference charts to show people what Asics trainer they need
     
    Last edited by a moderator: Jul 8, 2009
  28. Griff

    Griff Moderator

    Hi Raphael,

    Is the new improved article completed yet? I could not find it on your UK website whilst looking in the Knowledge section today. (Craig, don't look you'll get upset that the wet foot test still features heavily)

    Ian
     
  29. rmazoyer

    rmazoyer Welcome New Poster

    Hey Ian,

    Nope, we're still tweaking -- this is taking a ridiculous amount of time, but we've got a couple really good articles in the pipeline, so I hope it'll be worth the wait!

    -Raphaël
     
  30. rmazoyer

    rmazoyer Welcome New Poster

    All right, we're getting there!

    We just published a new article on gender differences: http://www.asics.co.uk/running/knowledge/running-shoes-reinvented-for-women

    Please let us know what you think of it!

    Also, the article on pronation is getting its final round of editing and illustrating, and will go to press very soon. Simon approved most of it: we still haven't gotten rid of the wet test, but are working on that as well.
     
  31. toomoon

    toomoon Well-Known Member

    In case, you have not seen it, here is the evidence on just how bogus that test is. Interestingly, in that thread, Simon said:I guess he must not have been talking avout ASICS[/QUOTE]

    I was talking about ASICS... and we do have a much better system... but.. unfortunately, sometimes the wheels grind exceedingly slowly, and that is why I am not anly going bald.. I am going white!
    All I can do is just continue to plug away for truth, justice and the podiarty arena way...
    s
     
  32. Simon:

    But Alfred E. Newman always said "What me worry?!":cool::drinks
     
  33. Mairead

    Mairead Welcome New Poster

    Hi all, finally we have worked out another version of our article on pronation, we'd like to have you guys cast an expert eye on it and tell us what you think.

    We've had alot of difficulty trying to find a good word for a person who has a pronation pattern that is neither overpronation or underpronation/supination, but who exhibitis an optimal amount of pronation.

    In the article a person with this type of pattern is called a "neutral pronator" but we feel this still off the mark. Any suggestions are welcome.


    The text of the article is shown below, the images are missing but they will illustrate the foot angle during stride for each type of pronation:


    "Pronation is the way the foot rolls inward when you walk and run. It is part of the natural movement that helps the lower leg deal with shock. Some people pronate more (overpronation) or less (underpronation) than others. Though this is not bad in itself, it does affect the way you run and it may increase the likelihood of injury. This makes your pronation pattern an important factor in choosing the right running shoes.

    Pronation
    Pronation occurs at the joint below the ankle, the subtalar joint. It describes the inward rolling motion of the foot just after it lands on the ground. This moment is called initial contact, which is part of the stance phase of the gait cycle. Learn more about the phases of gait in How We Run: The Gait Cycle.

    When you walk or run, pronation helps to attenuate the shock of initial contact. Without it, the full impact of each step would be transmitted up the leg and affect the normal mechanics of the lower limbs. Besides acting as a shock absorber, pronation also helps the foot “recognize” what type of ground it is on by stabilizing and adjusting the foot to the terrain type.

    Running shoes are designed today specifically for different pronation patterns. When you pick your next pair of running shoes, your pronation type is a very important factor in your choice.

    The best way to find out how you pronate is to consult an expert, who will perform a Gait Analysis and then advise you on the best type of running shoes for your pronation pattern. Many experts will ask to see your old pair of trainers, as their wear pattern gives an indication of the way you pronate. Of course, other factors than pronation, such as weight, also play a role in choosing the best shoe.

    (Pronation pattern of a neutral runner image)

    You are likely to “neutral pronator” if the soles of your shoes show wear in an S-shaped pattern, from the outer (lateral) heel to the big toe. When you have a normal pronation pattern you can run in a wide variety of shoes, but specialised neutral running shoes offering cushioning and support are most suitable. The GEL-NIMBUS is leading cushioning model for neutral runners.

    Underpronation
    Underpronation, also known as supination, is when the foot doesn't pronate much. The outer or lateral side of the heel hits the ground at an increased angle, and little or no normal pronation occurs, resulting in a large transmission of shock through the lower leg. This lateral loading of the foot continues for the entire stance phase of gait, further affecting running efficiency.

    (Underpronation (also known as supination)image)

    Underpronators are likely to have excessive wear on the outer heel of their shoes, and the entire upper may be pushed over to the lateral side.

    As underpronators tend to be susceptible to shock-related injuries like stress fractures, you should choose a neutral running shoe with plenty of cushioning, for example the GEL-CUMULUS . The extra cushioning will lessen the impact of landing the legs have to endure when running. Underpronators should avoid shoes with dual density midsoles, such as DuoMax, since they tend to exaggerate the problem.

    Overpronation

    Overpronation is when the foot rolls in excessively, or at a time when it should not, for instance late in the stance phase of gait. In this case much weight is transferred to the inner or medial side of the foot, and as the runner moves forward the load is borne by the inner edge rather than the ball of the foot. This destabilises the foot, which will attempt to regain stability by compensating for the inward movement. In a kind of chain reaction, this in turn affects the biomechanical efficiency of the leg, especially the knee and hip.

    (Overpronation image)

    The shoes of an overpronator will show extra wear on the inside of the heel and under the ball of the foot, especially the big toe.

    Overpronators should consider choosing maximum support or structured cushioning shoes. Structured cushioning shoes provide a degree of stability and cushioning, whereas maximum support shoes are the most stable shoes you can get. Running shoes in both of these categories will help your feet distribute the impact of running more effectively. The GEL-KAYANO is a leading structured cushioning shoe, whereas the GEL-EVOLUTION is reliable model in the maximum support category.

    Acknowledgements: This article has been written under the guidance of Brice Newton, Product Marketing Manager Footwear at ASICS Europe and Simon Bartold, ASICS International Research Coordinator."


    End of article.
     
  34. Griff

    Griff Moderator

    Hi there,

    Thanks for the article.

    From the first paragraph:

    To me the use of the terms 'overpronation' and 'underpronation' should be removed completely. This terminology still suggests (to the public) that there is an 'ideal' amount of pronation... maybe there is but we dont know that yet and if you can't define 'normal pronation' (which we can't) then how can you, by definition, state what is 'too much' or 'too little'? Perhaps much better off just saying we all pronate differing amounts to each other, and also differing amounts during differing activities?

    I'm not sure the research agrees entirely with this...
     
  35. paradigmshiftfitness

    paradigmshiftfitness Welcome New Poster

    So.....

    For gait is there a minimum amount of STJ eversion required in degrees? Is this a 'it depends' issue as well (Terrain, shod or not, STJ axis etc etc)

    Anyone?

    Thanks,
    R
     
  36. Hi R the short answer for the minimum amount of pronation required at the STJ during weightbearing is as you though - depends.

    As activity changes the amount of pronation required will also be different and the ability of the body to regulate this andor have the ability to regulate this is where pathology may begin.

    ie where does the STJ pronation come from, muscle contraction of the Peronials Longus and OR Brevis this is more easily controlled by the body.

    If however the STJ pronation moment is comming from the ground reaction force is maybe much more difficult to regulate the amount of pronation.

    I hope that makes sense.
     
  37. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    Its activity dependent. If you walk in straight line your whole life, you probably only need a few degrees; however if you turn a corner, you probably need a few more; if you are an Olympic level high jumper, you probably need 50-60 degrees of eversion..... there is no normal.
     
  38. efuller

    efuller MVP

    When I was at the podiatry college, I had a student who had about 25 degrees of STJ motion on one foot and less than 5 on the other foot. That 5 degrees could have easily been at the ankle. This is all the clinical signs of a tarsal coalition. No radiographic studies available. He played intercollegiate sports and never had any problems with his feet. That's not to say that he wont have problems later, maybe, but he got around just fine without an STJ for quite some time. You can acheive "gait" with a peg leg. The question is, is there an increased stress somewhere else. We will tend to see the painful coalitions. We don't know how many symptomless coalitions are out there.

    Regards,

    Eric
     
Loading...

Share This Page