New Study Finds Group of Heel Striking Barefoot Kenyan Runners.

Not all that is barefoot is necessarily forefoot…

You may have seen our tweet yesterday and have read this article. Or maybe, because you are a foot geek, you have seen it already.

Here’s the summary: “Jan. 9, 2013 — A recently published paper by two George Washington University researchers shows that the running foot strike patterns vary among habitually barefoot people in Kenya due to speed and other factors such as running habits and the hardness of the ground. These results are counter to the belief that barefoot people prefer one specific style of running.”

The study reported a 72 percent rearfoot landing when running barefoot at endurance pace speeds supporting the notion that speed affects landing choice (faster speeds transitioned  the runners into more midfoot / forefoot landing).  Lieberman’s Harvard study which brought much of the forefoot strike principle to the western world was often based off of sub 5 mile paced runs.

It raises the question “ If barefoot IS better, and forefoot impact IS BETTER, then, what gives?”

We think the better response is:

• there are many variables (genetics, surface, speed, etc) that can influence foot strike patterns and this paper exemplifies that.
• Fore foot striking in runners does lessen impact forces.
• Forefoot striking does appear to accentuate any forefoot abnormality (ie: varus/valgus) that may be present (something we will continue to say until someone proves it otherwise).
• forefoot striking loads the posterior compartment of the lower leg (tricep surae (gastroc soleus complex)) to a greater degree

We like a mid foot strike, not because it is the middle road, but because it supports the notion in distance running that the entire foot tripod (which is more stable) engages the ground reducing solitary forefoot and rearfoot loading issues which each have their risks and challenges and allows for a more stable contact point for the body to negotiate over.  We have pounded sand on forefoot types, and the inherent risks of forefoot strike running with each of them, from our inception.  But, when it comes to midfoot strike there doesn’t appear to be much, if any literature out there to support our opinion.  Maybe now that the forefoot and rearfoot studies are out there maybe someone will find a tribe of midfoot strikers to support our rants.

We think the key is not necessarily strike position, but rather where the foot is hitting the ground relative to the body AND MORE IMPORTANTLY, having a competent foot and lower kinetic chain and core, along with the body’s ABILITY to absorb or attenuate those forces, no matter where the foot is striking the ground.

This is no doubt the 1st in a series of papers looking at this. It will be interesting to see where it goes from here.

Ivo and Shawn…  The Gait Guys

here is the link: http://www.sciencedaily.com/releases/2013/01/130109185856.htm

all material copyright 2013 The Homunculus Group/ The Gait Guys. Please ask to use our stuff and reference it appropriately. We know a guy named BamBam who helps people play nice.

More research on Forefoot Running: Forefoot Varus and the toe extensor muscles.

Lately we have all seen much in the news about the forefoot strike loading in runners and many of the proposals and rebuttals regarding injury rates.  Our dialogue less than 2 weeks ago on some of Lieberman’s recent comments (our blog article “Dear Dr. Lieberman”, click here) seem to be ringing true again. Here are just two more insightful and important studies when it comes to looking at some of the proposed ideas and causes of forefoot varus. Naturally, a thinking mind would wonder if some of these weaknesses in anterior and posterior tibialis muscles as well as extensor toe musculature, as proposed in just these 2 articles, are causal to the forefoot injuries that seem inevitable as Lieberman seems to suggest (again, see our blog post). Naturally, weaknesses and poor motor patterns of some or all of these muscles is going to create and insufficient and possibly inefficient and pathologic forefoot loads because of the forefoot varus foot type these muscular imbalances can functionally produce.  We have been pounding sand on this issue for years but still no one listens.  The medial research, as evidenced here is supportive of our theories and everyday clinical findings.

To summarize, ONCE AGAIN, not everyone is suited or possibly ready for forefoot load/contact/strike running.  And if you have injury or problems in doing so, don’t blame your minimalist shoe……. it is either a foot type that needs functional repair or a foot type that is fixed an must opt for midfoot strike.

There is SO MUCH MORE to this game than just strap on some minimalist shoes and start forefoot loading your way on your next run.  Buyer beware !

Shawn and Ivo…….. the gait guys……..two guys who are “Gandhi’d” regularly. 

“First they ignore you, then they laugh at you, then they fight you, then you win.”

- Mahatma Gandhi

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http://www.ncbi.nlm.nih.gov/pubmed/20307453

Foot (Edinb). 2009 Jun;19(2):69-74. Epub 2008 Dec 31.

Foot varus in stroke patients: muscular activity of extensor digitorum longus during the swing phase of gait.

Reynard F, Dériaz O, Bergeau J.

Clinique romande de réadaptation, SUVA Care, Av. Gd-Champsec 90, Sion, Switzerland. fabienne.reynard@crr-suva.ch

Abstract

CONCLUSIONS: The activity of extensor digitorum longus muscle during the swing phase of gait is important to balance the foot in the frontal plane. The activation of that muscle should be included in rehabilitation programs.

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http://www.ncbi.nlm.nih.gov/pubmed/16882899

J Bone Joint Surg Am. 2006 Aug;88(8):1764-8.

The contributions of anterior and posterior tibialis dysfunction to varus foot deformity in patients with cerebral palsy.

Michlitsch MG, Rethlefsen SA, Kay RM.

Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.

Abstract

RESULTS: The muscular contributor to varus deformity was the anterior tibialis in thirty feet, the posterior tibialis in twenty-nine feet, both the anterior tibialis and the posterior tibialis in twenty-seven feet, and another contributor in two feet. Seventy feet had varus deformity during both stance phase and swing phase. Of these seventy feet, twenty-five exhibited dysfunction of the anterior tibialis, twenty exhibited dysfunction of the posterior tibialis, and twenty-three exhibited dysfunction of both muscles. Therefore, the timing of varus was not predictive of the contributing muscle or muscles.

CONCLUSIONS: The current study demonstrated a higher prevalence of anterior tibialis dysfunction, both alone and in combination with posterior tibialis dysfunction, as a contributor to pes varus in patients with pes varus and cerebral palsy than had been reported previously. Dynamic electromyography provides clinically useful information for the assessment of such patients.

Biomechanist challenges idea that forefoot strike pattern reduces runners’ injury rate→

Cites lack of conclusive evidence

By Jordana Bieze Foster

http://www.lowerextremityreview.com/issues/may/biomechanist-challenges-idea-that-forefoot-strike-pattern-reduces-runners-injury-rate

“UMass researchers have demonstrated that, although forefoot strikers do not experience a vertical ground reaction force “impact peak,” they do experience impacts during running, albeit at lower frequencies than rearfoot strikers. This research, presented last summer at the American College of Sports Medicine meeting in Denver, suggests that because those lower frequencies are attenuated by muscle tissues, while higher frequencies are attenuated by bone, forefoot strikers may actually face a higher risk of muscle injury than rearfoot strikers.

Claims that loading rate is significantly lower in forefoot strikers than rearfoot strikers also may not be entirely accurate, Hamill said. He cited research from Iowa State University, scheduled to be presented in August at the annual meeting of the American Society of Biomechanics, suggesting that when natural forefoot strikers switch to a rearfoot strike pattern, their loading rate actually decreases.

Research, most notably the oft-cited Harvard study published in Nature in 2010, have found higher magnitudes of ground reaction force in rearfoot strikers than in forefoot strikers. However, Hamill noted, the heel is a much less delicate structure than the forefoot and therefore may be better suited to absorb higher forces.”

Dear Dr. Lieberman : Some vital facts on forefoot running are not being discussed.→

A clay pot sitting in the sun will always be a clay pot. It has to go through the white heat of the furnace to become porcelain. -Mildred Wite Stouven.

Today’s blog article is likely to bring flames to our feet, but we are not afraid of the heat.  At the very least we will settle for the heat this article may bring so that our work can get the recognition we feel it deserves and so the truth can be brought to light for the good of all mankind.

“Forefoot strike causes less impact force on the body,” says co-author Daniel Lieberman, Ph.D., a professor of human evolutionary biology at Harvard and scribe of a popular barefoot running manifesto in 2010. “People forget that running is a skill, and if you don’t run properly, you’ll get injured.”

Amen to that; we have been saying that for years before this all became popular talk …

We recently read this article in Men’s Health, yet another one supportive of minimalism running. And once again some of the most important facts are being left out. We just cannot sit here and watch the inaccuracies of minimalism and forefoot running continue to root themselves without policing. So, let us once again set foot into the raging battle.

According to the article (LINK) Sturtz says, “Landing on your forefoot, the way humans have run for thousands of years, produces almost zero impact on joints and bones, according to Lieberman’s 2010 study. But 75 percent of us now land heel first—cushioned running shoes made that possible (and comfortable)—which slams up to 3 times the body’s weight in impact force on your knees and legs.”

Our question is, “ Why is no one paying attention to foot types?” In every lecture we do, to clinicians or everyday runners, about “forefoot type” variants (valgus and varus to be precise) we comment that this is something that should be talked about during Running Form Clinics where forefoot landing is promoted. 

“… forefoot running is not the whole answer to injury prevention, just a component”, says Lieberman. “This is not a simple solution to a complex problem—you can’t change one thing and have everything be fine. You can still forefoot strike with poor form.”

And we would add to that quote that “you can get a resultant compensatory running form if you forefoot strike with a forefoot varus or forefoot valgus”. Not everyone has that pristine neutral forefoot bipod architecture that the internet articles are assuming exists in everyone, and thus there is no way that everyone has fully competent pristine forefoot biomechanics that will not eventually trigger injury. This is a fact, not our opinion. 

Dr Lieberman then goes on to say: “ If it ain’t broke, don’t fix it.”

We respectfully disagree. We do this on a daily basis (as do many of you).  If the check engine light on your dashboard is flashing at you every day for a week you would be remiss not to consider the repercussions.  “The car ain’t broken… YET” is a more precise comment. You would be wise not to go on a long distance car trip knowing this fact.  Translating this to forefoot load/strike running, ignoring a potential injury because of flawed forefoot anatomy and biomechanics is a recipe for injury.  Just because it isn’t broken YET doesn’t mean ignoring the issues will make them go away or make you immune. A few hundred or thousand miles on a forefoot variant can be an issue clinically and injury wise.

Just because the body isn’t broken YET doesn’t mean it cannot work better and prevent a problem down the road. Dr Lieberman then goes on to quote, “Remember, almost every distance runner gets injured".  Why is he batting from both sides of the plate here? If “Landing on your forefoot, the way humans have run for thousands of years, produces almost zero impact on joints and bones”, according to Lieberman’s 2010 study then why would he go on to say “Almost every distance runner gets injured”?  There has to be a reason !  Forefoot running is either the answer or it isn’t.  Our valid and ignored proposal above, and our repeated comments throughout our 500+ blog posts on this topic on foot types, is a valid answer to his injury assumption.  It is quite possible that these inevitable injuries occur because people take the advice of “if it ain’t broken, don’t fix it”.  It is also most likely that ignorance of the deeper facts is bliss for most people. .Had they spent the time to find out about their forefoot type and learn to modify subtle biomechanical flaws of forefoot loading strategies of their foot type, perhaps we wouldn’t hear “Remember, almost every distance runner gets injured".   Maybe that is why you SHOULD look into fixing things that are not YET broken and at the very least learn about foot types, particularly which one you have and the potential risks it exposes you to. Our blog here has done this in depth over the last year. 

“An ounce of prevention is worth a pound of cure” -Benjamin Franklin.  Anyone is medicine knows this is true (or should).

We prefer midfoot strike when possible, for many reasons but mainly because it takes into account a tripod contact loading response.  A tripod load is more stable than a rear foot unipod load and more stable than a forefoot bipod load, particularly when there are rear or forefoot variants (rearfoot valgus, rearfoot varus, forefoot valgus, forefoot varus) from the pristine normal that is always assumed in many articles.   A tripod loading response (midfoot strike) can dampen some of the mechanical flaws of either heel or forefoot strike patterns and of the foot type variants that are the norm, not the exception.

We see this stuff everyday in our practices. We are the guys that get the injury cases that are driven by the inaccuracies, or better put “overlooked facts”, of articles on the internet. To be fair, we have also written a fair number of articles for magazines and we know how they can get so chopped down that truth, honesty and full disclosure can be lost for the sake of publication limitations. None the less, our strong opinion, this article could have been far more complete had it talked about the issues we have brought to light here.  We love and respect the work of Lieberman and his colleagues.  He and his colleagues have done a huge service to the runners of the world and we have learned from them. Learning is a lifelong journey for us all and we just think that there is a huge information gap that is being missed and we feel it is time that the runners of the world hear the whole truth. We believe our work is filling that gap.

“First they ignore you, then they laugh at you, then they fight you, then you win.”

- Mahatma Gandhi

For the past year, we have been feeling a bit like Gandhi must have felt. We realize that some of our work is complicated, difficult to understand, and tough to digest. We know we are laughed at by some who prefer to seek the safety of ignorance. And yes, despite 600 blog posts on these very topics (yes, we have one of the most informative blogs and YouTube Channels on the web for runners and athletes looking for answers) we feel somewhat ignored. None the less, we continue to stick our necks out far and long to set the record straight to make sure that everyone knows the facts they deserve to know.   We hope you will forward, link, Facebook and tweet the hell out of our blog post today, for the good of every runner and athlete you know and for the whole of mankind.  We are in this for the long haul. Stick and stones … .       - Drs. Shawn and Ivo …  The Gait Guys

here is the article that spurred our post:

http://news.menshealth.com/fix-your-running-form/2012/01/24/

Shod vs. Unshod : What the Lieberman-Harvard study really said.

Shod vs. Unshod : What the Lieberman-Harvard study really said.

Thanks to OwenAnderson of  Educatedrunner.com for this excellent article.

http://educatedrunner.com/Blog/tabid/633/articleType/ArticleView/articleId/797/BAREFOOT-RUNNING-WHAT-THE-HARVARD-STUDY-REALLY-SAID.aspx

If you are paying attention to everything that is going on, you want to read this well thought out article.  The Gait Guys are digesting this article and we will render our thoughts and opinions shortly.  But, differing points of view, when laid out logically and with sound reason, deserve consideration. This is how the truth is eventually discovered.

Give this article a productive and attentive read.  We will get back to you shortly.

Summary statement seems to be this….. (quoted word from word from the article).

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“Ironically, the popular press has been using the Harvard study as a launching pad for the idea that barefoot running is healthier than shod ambling, even though Lieberman’s paper provided no data at all to test the idea that barefoot running lowers the risk of running injuries!

  Here’s what Lieberman et al actually found:  

(A) Habitually shod runners (groups 1 and 5 from above) who grew up wearing shoes are usually rear-foot strikers (RFS), meaning that their heels make the first impacts with the ground during running, right at the beginning of the stance phase of gait. This is not new information. The strong link between running in shoes and heel-striking has been known for many years.  

(B) Runners who grew up running barefooted or who switched to running barefooted (groups 2, 3, and 4) are generally fore-foot strikers (FFS), meaning that they tend to land initially on the balls of their feet while running, after which their heels drop down to make contact with the ground. Again, this is nothing new – the tight connection between barefoot running and FFS (and also MFS, mid-foot striking) has been general knowledge for years.  

© Impact forces transmitted through the foot, ankle, and leg immediately after impact with the ground are about three times greater in shod runners using RFS, compared with barefoot runners with FFS. Some – but not all - previous studies have shown this same relationship, with RFS producing greater impact force during the first portion of stance, compared with MFS and FFS. The sudden rise in force with RFS, immediately after ground contact, is known as the “impact transient.” The disparity in impact transient between barefoot and shod running represents a “foundation” for the belief that barefoot running is “safer” and less injury producing. While this appears to be logical thinking, it is important to know that no study has ever shown that greater impact forces during the first portion of stance magnify the risk of running injury.  

(D) Rates of loading of impact force are actually quite similar between shod RFS runners and barefoot FFS athletes (Figure 2b from the Nature paper). The rate at which impact force is loaded into the leg has also been suggested to be a risk factor for injury, although convincing proof of this notion does not exist.  

(E) During the early stance phase of barefoot FFS running, there is greater knee flexion, greater dorsi-flexion at the ankle, and a 74-percent-greater drop in the center of mass, compared with shod RFS running. “Vertical compliance” is defined as the drop in the runner’s center of mass relative to the vertical force during the impact period of stance, and it is obviously greater in barefoot FFS running, compared with shod RFS. Vertical compliance varies as a function of running-surface hardness, and this is why force-loading rates are similar for barefoot FFS runners over a wide array of running surfaces (the runners adjust compliance according to surface). This is not novel information, however.  

(F) During barefoot FFS ambling, the ground reaction force torques the foot around the ankle (and therefore increases the amount of work carried out by the ankle, compared with shod RFS running). With shod RFS running, the ankle converts little impact energy into rotational energy. Potentially, this could spike the rate of ankle-area injuries (for example in the Achilles tendon and calf) for barefoot runners, although this hypothesis has not been tested.  

And that was pretty much it! The Nature investigation did disclose some interesting information about the effective mass of the foot and shank (which we won’t discuss here), but it offered no other information about the potential links between barefoot running and either injury or performance.   And that’s why it’s too early for you to consider changing from shod to barefoot running, unless such a shift would be a lot of fun for you. 

There’s just no proof that barefoot running will reduce your risk of injury or make you faster.   In fact, it’s important to remember that most injuries in running are caused by an imbalance between the strain and micro-damage experienced by a muscle or connective tissue during training and the tissue’s ability to recover from such stress. This imbalance can occur when training is conducted shod – or barefooted! A weak or overly tight hamstring muscle which has been undone by excessive mileage won’t care if its owner was running barefooted or wearing shoes – it will still feel the pain. ” -

Owen Andersson, http://educatedrunner.com/Blog/tabid/633/articleType/ArticleView/articleId/797/BAREFOOT-RUNNING-WHAT-THE-HARVARD-STUDY-REALLY-SAID.aspx