Brooks On The Level

Oct. 25 Articles, Shoes no comments

Brooks is teaming up with the New England Running Company to hook one lucky subscriber up with a pair of shoes and an accessory in this month’s giveaway. The winner will get to choose from the wide selection at the New England Running Company store. If you don’t live anywhere near the store, don’t worry. The prize can be shipped to you.

As always, the contest is for subscribers only but there will be chances to gain additional entries via social media. For instance, any subscriber who mentions us or retweets us on Twitter will gain an additional entry. On Facebook, all you have to do is share one of our status updates. While we’re throwing links out there, be sure to follow both Brooks and New England Running Co on Twitter too.

We’ll give the goods away sometime next week (before Halloween). Until then, you can find the latest and greatest Brooks gear at the New England Running Company in Beverly, MA.

Choosing the Right Running Shoes

May. 24 Articles, Shoes no comments

A Look at How Trainers Affect Training and Running Performance

Guest blog by Matt Phillips, RunnersConnect

running shoes Following last week’s article “Foot Types & Foot Wear,” I have had quite a few runners ask me the same question, with words to the effect of: “Ok, if the whole overpronation shoe model thing has no evidence, what the hell do I run in!?”

A very good question! But first things first…

Why do we need running shoes at all?

Relax, I’m not going to start preaching about barefoot running (although I’m not going to dismiss it either). But in order to discuss how we decide which trainers are suitable for us, it is useful to re-evaluate exactly what we are buying them for.

With that in mind, over the last couple of days I have been asking the runners I meet what they are looking for when they buy trainers. Collectively, the majority of them produced the following three reasons: protection,support, cushioning.

Protection

If by protection we are referring to avoiding glass & syringes, then wearing something on our feet obviously makes sense. This may well be the main contributing factor as to why, at least in my experience, it is rare to see runners training or racing in no shoes on at all.

Many of us could probably find less hazardous routes on which to entertain the theoretical benefits of barefoot running, but until clearer evidence supports such theories, most of us will probably pass. However, if we’re talking about protection from running on hard surfaces then we are essentially looking at cushioning (more on that shortly).

Support

By support, most people are referring to stopping the medial arch of the foot “collapsing,” which brings us back to the whole supination/neutral/pronation paradigm used by most running shops to prescribe you a “suitable” trainer after watching you walk or run for a couple of minutes (or in some cases just standing you on a pressure pad, which in itself has no connection to how your foot acts whilst running). I am sure you are already familiar with the process:

If the arch of your supporting foot drops “too much” you are labelled an “overpronator” and assigned a motion-control shoe that will in theory reduce the “overpronation”.
If your arch does not drop “enough”, you are said to be an underpronator (or supinator), and assigned a flexible, cushioned shoe to absorb some of the shock that underpronator is said to cause.
If you are somewhere in the middle, you are said to have normal pronation and are recommended a “neutral” shoe that in theory provides just the right amount of stability and cushioning.

As we saw last week, this model is heavily flawed and unsupported to date by any evidence. It is important not to let fear of injury or promises of recovery persuade you to be herded into one of the three pens (motion control, stability or neutral) however persuasive the sheepdog/sales person may be!

Cushioning

If you regularly run on hard surfaces like pavements, tracks and treadmills, you would think cushioning makes sense. Running shops can be very quick to stress this point if they “see” you as a heel striker. And yet, studies show (Scott, 1990) that peak loads at typical sites of injury for runners (Achilles, knees, etc.) actually occur during midstance (when your bodyweight passes over the supporting leg) and toe off (when your back leg pushes away from the ground).

These studies suggest that impact force at heel contact has no effect on the peak force seen at typical injury sites.

There is also growing evidence that when faced with higher impact forces from a harder running surface, your body makes natural adjustments to deal with the change in impact force – changes in joint stiffness, changes in the way the foot strikes the ground, and also via a concept called “muscle tuning” (pre-activation of muscles prior to impact).

Based on information received visually and from the previous foot strike, the body adjusts how strongly the muscles in your leg contract before the foot hits the ground again. Imagine jumping on a trampoline – your legs naturally stiffen in preparation for the soft landing.

Now imagine yourself jumping onto concrete – your legs naturally become less stiff in preparation for the hard landing. This natural adjustment is the result of sensory feedback from not only the eyes but also from the feet. In other words, the theory is that sensory feedback from the feet following one foot strike helps prepares the body for the next foot strike. If this is indeed the case, could excessive cushioning at the bottom of a trainer inhibit this natural sensory feedback?

Cushioning & injury prevention

The role that impact actually plays in running injuries is not at all clear. Studies by two highly respected biomechanics researchers, Dr. Irene Davis (Director of the Running Injury Lab, University of Delaware) and Dr. Benno Nigg (Co-Director of the Human Performance Laboratory, University of Calgary) have produced contrasting results.

Whilst Dr. Davis’ research links high impact loading rates with plantar fasciitis and tibia stress fractures, Dr. Nigg has found that overall injury rates are slightly lower among runners with high impact loading rates.

One possible interpretation of the above is that leg stiffness, as we considered earlier, is an important factor with certain injuries. Dr. Davis’ research linked runners who had suffered tibia stress fractures with higher impact forces and higher leg stiffness.

If tibia stress fractures are a consequence of high leg stiffness (for which I hasten to add there is as yet no evidence) then maybe runners susceptible to them should try wearing a less cushioned shoe and run on harder surfaces.

Just as we saw in our “landing on concrete” example earlier, in preparation for the harder surface, the body will reduce leg stiffness, which if the theory is correct could reduce susceptibility to tibia stress fractures.

At this stage it is all theory, and I draw particular attention to the words “maybe” and “try”. Always introduce changes slowly and gradually! Give your body a chance to tell you how it feels about the change before you do any harm to yourself!

So what trainers should I buy?

For those of you still clinging onto the hope that I or indeed anyone is going to be able to give you a structured model for trainer selection, I should probably put you out of your misery. There is no model. But do not despair. See it as liberation as opposed to a hindrance.

Yes, some people are recommended trainers and their injury disappears, but plenty are given the same advice and the injury continues. The journey to injury free running is best started with acceptance & application of the following mantra, as used by running coach James Dunne of Kinetic Revolution: Form Before Footwear.

As far as trainer selection goes, Pete Larson, anatomy professor, writer & runner with self diagnosed shoe obsession sums it up nicely: “I can run in just about anything as long as I’m careful to take things slowly and listen to my body.”

This is what I mean by “liberation.”

Part of Pete’s Running Shoe Collection, 2010. (Photo Courtesy of P. Larson)

In my opinion, one of the best things to so far emerge from the barefoot debate is the much larger variety of designs of shoe you can now choose from.

Having seen that heavy cushioning is not necessarily helpful to everybody, you should now hopefully be more confident to test, for example, some lighter trainers. Again, the secret is experimenting to see what feels comfortable for you. Bear in mind that a trainer that suits you for one distance, terrain or speed may not work as well for another.

You could also try trainers with a slightly lower Heel-Toe Drop than you are used to (the difference in height between the heel and the forefoot).

Traditional running shoes have a heel-toe drop of about 12mm. Vibram Fivefingers have pretty much a drop of 0mm. Going straight from 12mm to 0mm is not taking things slowly or listening to your body! There are plenty of 6-10mm transitional trainers on the market which will allow you to experiment more gently.

Though there is as yet no direct evidence for benefits of a lower drop, I personally see much logic in the argument that exposing your feet and legs to varying forces (in a controlled, sensible manner) could potentially make you a stronger runner and reduce injury.

Remember to listen to your body

If you run too far, too often, or too fast in a new pair of trainers, your body will let you know. Many of the running injuries we see in clinic are linked to a runner buying a new pair of trainers and thinking they can pick up their training program from where they left off. It’s more than that. Most runners actually run faster or further the first time they put on their new trainers (we all love new toys!).

It is vital to respect the fact that your body will often need time to adjust to a new style of trainer. Put on a minimalistic shoe for the first time and run too far and your calves will soon let you know about it! It’s all about taking it slowly and listening to your body.

If you experience a slight discomfort, treat it as a thoughtful message from your body that you need to break the new trainers in a little more gently. Put them away for a while. Go back to your favourite trainers then re-test the new ones with reduced time or intensity.

Obviously, if the pain is persistent and affects your running whilst wearing other footwear then get it checked out by a professional, but in my experience most running injuries are the result of either ignoring a warning sign (not listening to the body) or too quick an escalation in frequency, intensity or time.

It may be the shoes, but it’s more likely to be you pushing yourself too much, too soon. Which brings me to my next point…

Use more than one pair of trainers

In order to break in new trainers, you will need to have your all time favorites at hand to wear in between. Your body will warn you if you are doing too much in your new trainers. Listen to it. Put them away for a week, continue with your regular trainers, then go back to the new ones.

Many runners I work with report that exposing their legs & feet to different forces via rotating the trainers they run in leads to (or at least coincides with) less injury. Given that the majority of running injuries are the result of repetitive strain, mixing it up kind of makes sense (and that goes for running surfaces as well). Invest in a few pairs of different style trainers – the chances are you will get your money back by less need for injury treatment!

Have you experienced success by changing to a new style of trainer? Maybe you already rotate different style trainers as part of your running program? We are always keen to hear from you and look forward to reading your comments.

Happy running!

Matt Phillips is a Run Conditioning Coach, Video Gait Analyst & Sports Massage Therapist with over 20 years experience working within the Health & Fitness Industry. Follow Matt on Twitter. And for more great training, nutrition, maintenance info, check out the RunnersConnect blog.

Injury Prevention: Footwear & Foot Type

May. 17 Articles, Shoes 2 comments

The Impact of Footwear and Foot Type on Injury Prevention

Guest blog by Matt Phillips, RunnersConnect

footwear “Always Evolve” – one of my favourite valedictions used by esteemed physical therapist and blogger Mike Scott, DPT at the end of posts in his weekly series “Educainment.”

Running has certainly seen some evolution of thought over the last few years, much of it following the publication in May 2009 of Christopher McDougal’s best seller Born To Run, bringing with it bold claims that running barefoot (or wearing something as close as possible to barefoot while protecting you from environmental elements) can strengthen your feet, reduce running injuries, encourage proper running form, and improve performance.

Until then, the only experience many of us had of barefoot running was seeing the South African teenager Zola Budd on our television sets, running barefoot in the women’s 3000 meter race at the 1984 Los Angeles Olympics.

Barefoot running

Whilst some runners have praised a transition to barefoot running (along with the typical shift to forefoot striking that barefoot running encourages) as a cure for an injury they were suffering, others have not been so fortunate and have seen it bring the onset of new injury, despite religiously following a slow, progressive transition period.

Clinical tests to date have also produced conflicting results. Barefoot running has been seen to reduce the risk of certain running related injuries, but increase the risk of others. It’s as if what works for some does not necessarily work for others. Sound familiar?

Regardless of personal experience, production of conclusive evidence for the benefits of barefoot running is still an ongoing project.

Minimalistic footwear

The increased profile and interest in barefoot running brought with it demand for less restrictive, less cushioned footwear, with the idea of allowing the foot to move and work in a more natural fashion whilst still providing a certain amount of protection.

As a result, today there is a wide spectrum of minimalistic footwear that, though not as extreme as barefoot style shoes like the Vibram FiveFingers, typically aim to provide less drop (difference between heel height and toe height), less cushioning, a wider toe box (more room for the toes) and more flexibility.

Like barefoot running, conclusive evidence for the benefits of minimalistic footwear is still a work in practice. A 2012 review in the Journal of Strength & Conditioning titled: “Running Barefoot or in Minimalist Shoes: Evidence or Conjecture?” concluded:

“Running barefoot or in minimalist footwear has become a popular trend. Whether this trend is supported by the evidence or conjecture has yet to be determined.”

Traditional footwear

Before any of you take “lack of conclusive evidence” as a reason to dismiss the possible benefits of barefoot running or minimalist shoes, I should point out – and this may come as a shock to you – that there is no evidence either that traditional running shoes can reduce injury or improve running performance.

Yes, you read that right. Though you were maybe told in the sports shop that your cushioned, stability or motion control trainer will help prevent injury, there is no evidence to support it. The problem is, the model that has been used for the last sixty years and more often than not is still used to help you select which trainers suit you is based on, well… not a lot.

Foot types

If you have ever been to a sports shop to buy a pair of running shoes (or have received an “ankle-down” gait analysis), chances are you are familiar with the diagram below, or something very similar. It links three “foot types” (based on the height of the medial arch) with three corresponding types of recommended running shoe:

RC6_FootTypes

The origin of the idea to group feet according to the height of the medial arch is not clear. Ian Griffiths, Director of Sports Podiatry Info Ltd suggests it may stem from a method of assessing footprints devised in 1947 by Colonel Harris and Major Beath as part of an Army foot survey. The first time an image associating medial arch height with shoe type actually appeared in print could have been the 1980 “The Running Shoe Book” by Peter R Cavanagh.

RC6_RunningShoeBook

What we do know is that since 1980, running shoes all over the world have been recommended and sold using the Foot Type model. Selection typically follows an “assessment” (often involving the subject stepping onto a pressure pad or being filmed from the ankle down whilst running) of how much the medial arch drops (referred to in the diagram as “pronation”) or doesn’t drop (“supination”), along with the idea that somewhere in the middle (“neutral”) is normal, healthy and necessary for injury prevention (more on that later).

If the arch of your supporting leg drops “too much”, you are labelled an “overpronator” and assigned a motion-control shoe that will in theory reduce the “overpronation”. If your arch does not drop “enough”, you are said to be an underpronator (or supinator), and assigned a flexible, cushioned shoe to absorb some of the shock thatunderpronator is said to cause.
If you are somewhere in the middle, you are said to have normal pronation and are recommended a “neutral” shoe that in theory provides just the right amount of stability and cushioning. Leaving aside the question of who decides “how much” dropping is normal, it is important at this stage to remind ourselves that both pronation and supination are natural, integral parts of foot biomechanics.

Dr Shawn Allen, Diplomate of American Board of Chiropractic Orthopaedists explains:

“The foot is a biomechanical marvel. 26 bones and 31 joints, working together in concert to provide balance, stability, and locomotion. As we walk or run, the foot is supposed to go through a series of biomechanical changes, so that it can either adapt to the environment or become a rigid lever for propulsion. When these mechanisms fail, problems usually arise. When the heel hits the ground, the arch of the foot is supposed to partially collapse (pronation), so that the foot can adapt to the ground; in this position, it is flexible and “unlocked”. After the weight of the body passes over the foot, the arch is supposed to retract, and the foot becomes more rigid or “locked” (supination), so that you can use it to propel yourself forward. If the foot remains in pronation for too long, or does not supinate correctly, problems will develop over time.”

Problems with assigning shoes according to degree of pronation

So, the running shoe recommendation model is based on the idea that at midstance, just before the full weight of the body passes over the foot, the best position of the subtalar jointis “neutral”, i.e. the foot perpendicular to the horizontal ground.

The argument is that this “neutral” position signifies optimum functioning of the foot, optimum pronation and supination. One problem with this is the fact that the subtalar joint has variable anatomy. In other words, function will vary from person to person, so the ‘optimum’ position to be in will also vary. Ian Griffiths explains:

“Studies have shown that the structural anatomy of the human subtalar joint varies from person to person and it has also been shown that the location of the axis of the joint can and does vary from person to person; this will of course directly influence the magnitude of pronation and supination seen. In light of this sort of evidence it seems odd that there would be an expectation that all individuals could or should function similarly or identically.”

Taking the above into consideration, it should come as no surprise that there is no data or evidence that suggests “neutral” STJ alignment is linked with injury and/or pain free running. One study examined 120 healthy individuals both non weight-bearing and weight-bearing. Not one subject conformed to the criteria of “neutral” alignment.

Is there any evidence that “over-pronation” increases injury?

Almost all studies to date on “over-pronation” have found no evidence that it increases the risk of injury. A 2010 study concluded that the prescription of shoes with elevated cushioned heels and pronation control systems tailored to an individual’s foot type was not evidence based.

Another piece of research suggested the running shoe model was overly simplistic and potentially injurious. In fact, in this research, every ‘overpronated’ runner put into a motion control shoe during a 13 week half marathon training programme reported an injury.

Craig Payne, DipPod MPH, University lecturer and famed Running Research Junkie points out that lack of evidence for linking overpronation to injury may well be down to the methods used to measure pronation:

“The weakness of many of those studies is how they measured “pronation”; for example, some measure calcaneal eversion; some measure navicular drop; some do a footprint analysis; and some use a dynamic 3D kinematic analysis. The problem with that is that someone may be ‘overpronated’ on the measurement of one parameter and not ‘overpronated’ on another parameter.”

A study published this month by Teyhen DS. titled “Impact of Foot Type on Cost of Lower Extremity Injury” set out to determine the relationship between foot type and medical costs associated with lower extremity musculoskeletal injury, using a population of 668 healthy U.S. military healthcare beneficiaries in active military service for at least 18 months of the 31 month study.

It quantified level of pronation using the Foot Posture Index, a measurement of static foot posture that takes into account not one but multiple components that go into “overpronation”, devised by Dr Anthony Redmond, Arthritis Research Campaign Lecturer at the University of Leeds.

Whether static foot posture has much to do with foot posture whilst moving (e.g. running) is a discussion for another day. What the study did show is that of the 336 participants (out of the total 668) who sought medical care for lower extremity musculoskeletal injuries, a high percentage (no exact value available at this time) were those who had been listed as “extreme pronated feet” via the Foot Posture Index.

Future research will be needed to help see if degree of pronation via multiple component assessment (e.g. the Foot Posture Index) can be linked to injury. In the meantime, using just one component of “over-pronation” (e.g. medial arch height) to assign suitable footwear will continue to be a game of hit and miss.

Concluding considerations

Is the whole running shoe recommendation model based on misconception?
If it is, what model should be used, if any?
There are certifications out there teaching shop staff how to sell running shoes. What are they based on?
As a result of this debate, some are suggesting that runners should buy trainers based on “comfort” alone. Hard to imagine?

As I see it, just because an injury is present on someone with an “excessive” level of pronation (whatever that is…), it does necessarily mean that the level of pronation is the cause of the injury (correlation vs. causation).

It is imperative to consider and understand the biomechanics of the rest of the body (as well as foot posture) before reaching any conclusions. And even with all of that knowledge, it will still be a daunting task to be able to say “this is the running shoe you need!”

So, what should we base trainer recommendation on? A tricky question that we will consider next week. In the meantime, I am keen to know of your personal experience. What you are currently running in? What made you buy them? Have you managed to reduce injury via a change in footwear? Maybe a change in your footwear has led to an increase in injury? As always, I look forward to your comments!