Physical therapists who always preach "more stability is better"....Are they really helping ALL runners?

I read an article in the magazine ADVANCE for Physical Therapy & Rehab Medicine the other day that had a great premise but was not very inclusive.  The article "Solid Footing" fell short in a few ways.  Read my published commentary below for my thoughts on the article.  I have also attached the link to the article + commentary for your convenience.

http://physical-therapy.advanceweb.com/Archives/Article-Archives/Solid-Footing.aspx

Commentary:

Gait analysis with high-speed video equipment is certainly a valuable tool when treating the injured runner.  This article hits that point on the head.  I disagree with a few of the other points presented, however.

First, if the runner is dealing with an injury that is a direct result of poor biomechanics, the first step of action is not always to provide him with the most support possible.  The symptoms associated with some injuries can change very quickly (for the better) when the source of stress is eliminated.  Such sources of stress include, but are not limited to, excessive pronation, heel striking when compared to mid-foot or forefoot striking, and significant peak hip adduction and hip internal rotation in stance.  As the authors stated, some runners may need more support initially, but what they failed to mention is that there are others who may benefit from less support.  For instance, a patient who is struggling with persistent knee pain may need to adjust his footstrike kinematics in order to eliminate the impact transient at initial contact.  Take a close look -- is the patient heel striking, contacting the ground significantly outside his center of gravity aka overstriding?  The proper way to eliminate that impact transient is not to provide him with a more supportive or cushioned shoe but rather to teach him how to contact the ground lightly underneath their center of gravity.  Applying this principle is quite simple.  Within the session, trial test barefoot running on a smooth grass or carpet surface.  If the patient experiences a reduction in symptoms, his injury is most likely related to footstrike kinematics, and a rehab program that involves performing balance activities and other stability exercises barefoot as well as short barefoot strides on grass (50-100m) will promote the development of a mid-foot or forefoot strike.  If the runner does not experience a reduction in symptoms, then maybe the clinician does want to look into stability shoes or even an orthotic….but not until barefoot running has been trial tested.  As physical therapists, we do not want to promote reliance upon external devices if they are not truly necessary.  The human foot and ankle is a marvel and was created to be functional on its own.  Physical therapists can help injured runners develop a healthier, more stable foot and ankle complex through proper exercise prescription.

Which leads me to my second counterpoint…why would the authors attempt to promote a forefoot strike among injured runners while they are wearing heavily cushioned and supportive shoes?  A high heel-forefoot drop, which exists in almost all stability shoes, encourages a heel strike.  The human body will take advantage of what it is given; therefore, if more cushioning is placed in the heel of a shoe, runners will initially contact the ground in that area of high cushioning.  Compare that to barefoot runners or those who run in more minimalist footwear.  They would not dream of heel striking as their calcaneus would be unable to repetitively bear such a load without bony injury.   So, if we try to have runners who are wearing heavily cushioned and supportive shoes forefoot strike, what are we doing?  We are certainly placing an awkward load on the Achilles tendon as it is in a shortened state throughout.  We should be encouraging the Achilles to lengthen through its normal range of motion so that more elastic energy can be stored before push-off in late stance.

These are just some thoughts for discussion and to highlight that there is more than one approach when an injured runner comes to a clinic’s door.  The clinic that considers both approaches is going to be the one that helps that runner return to running more efficiently and effectively.

Should ALL runners stop heel striking? Delving beyond footstrike....

In my last post, we discussed some of the underlying causes of running injuries -- poor biomechanics being one of them.  Today I'd like to delve a bit deeper into running biomechanics.

First, several different running footstrikes exist: heel striking, mid-foot striking, and forefoot striking.  If you went to your local 5k and observed the footstrikes of all the runners, you would quickly notice that almost everyone is heel striking.  Most recreational runners in the USA are heel strikers, which is likely a result of wearing cushioned shoes all their lives (with significant amounts of cushioning in the heels of the shoes).  Besides having poorly developed muscles within the foot, these runners might also overstride when they are running.  In many third-world countries where shoes are not as plentiful, individuals tend to be mid-foot or forefoot strikers while running.  Adoption of a mid-foot or forefoot strike is absolutely necessary because a barefoot calcaneus (heel) cannot repeatedly bear the load of our body at the point of initial contact; a healthy arch, on the other hand, is more than capable of bearing this load, which is what occurs during barefoot running.  Therefore, the availability and our choice of footwear certainly impact how we run.

Now, let's take a look at the differences between a heel strike and a mid-foot strike.  I've taken high-speed video using Dartfish software to provide you with a visual representation of each footstrike.  You'll notice in the top video (shod) that the runner contacts the ground first with the heel....and then rolls through onto his toes, at which point he pushes-off.  Conversely, in the bottom video (barefoot), the runner contacts the ground on the outside of his mid-foot....before flattening the foot and then rolling towards his toes to push-off.  Also, take note of where the runner's foot is landing in relation to his center of gravity (location of his pelvis) in each video.  A mid-foot strike forces the runner to strike more under his center of gravity than does a heel strike.  Why is center of gravity important in running?  Just like when we lift a heavy object from the floor, the point at which we initially contact the ground while running should be only slightly in front of our center of gravity (otherwise we are overstriding).  If it is not, we subject our lower extremities to significantly greater impact forces.  However, you can heel strike while still landing optimally under your center of gravity.  In this case, heel striking does not appear to be as bad as many make it out to be.  Unfortunately, very few runners are truly capable of heel striking without overstriding, which may be a result of our footwear.  On the other hand, it is nearly impossible to mid-foot or forefoot strike and overstride...hence the reason why many encourage a switch from heel striking to mid-foot or forefoot striking.  [Note: the current literature has determined that heel striking generates greater impact forces than mid-foot or forefoot striking even if you are wearing a well-cushioned shoe.]

Whew.  That is a lot for anyone to absorb all at once.  Contemplating these points though, many runners ask me whether they should switch from heel striking to mid-foot or forefoot striking.  My answer -- it depends.  It depends upon whether you are currently injured or running pain-free.  It depends upon your running goals.  It depends upon whether you are actually overstriding.  There are too many factors to consider to make a blanket statement for everyone.  What I will say is that many runners could benefit from including barefoot strides and drills on a smooth, grass field (excluding diabetics!).  This barefoot running will reinforce your "natural" biomechanics and help develop the many muscles in the ankle and foot.  You should use it as a SUPPLEMENT to your regular training regimen....just like you might supplement your training with strength training or core work.  Remember, build up slowly.  Start with one 50-100 meter barefoot stride and increase by one each week until you are running 8-10 barefoot strides total following a run.

Let me know your thoughts on the footstrike debate.  I'd be interested in hearing your experiences or stories regarding barefoot running.

Another great minimalist shoe - Merrell Trail Glove!

Recently, I decided to purchase a pair of the Merrell Trail Gloves.  I have worn a variety of minimalistic, "low-profile" shoes since December 2004 and continue to run by the mantra "less is more".  Although I recognize that such minimalist shoes are not for everyone, many runners could certainly benefit from supplementing their training with barefoot and/or minimalist running.  One of the key benefits of running barefoot or in minimalist shoes is the lack of (or very little) heel to forefoot drop.  Regular trainers have a greater amount of cushioning in the heel of the shoe than in the forefoot; as a result, the Achilles tendon is constantly in a shortened state throughout the gait cycle.  Why is this bad??  The same reason that high heels are terrible for a woman's feet.  A chronically shortened Achilles tendon does not produce the same amount of propulsion as does one of normal length.  Also, transitioning from high-heeled trainers to flats or spikes sans injury is much more difficult.  Training exclusively in more minimal shoes or including them in your training shoe rotation a few times a week can help you avoid these pitfalls.  Remember, as with everything, a VERY GRADUAL transition is necessary to avoid injury, however.

Anyways........the reason the Merrell Trail Glove is so special is because it has a zero heel-forefoot drop!  In other words, 12 mm of cushioning exists in both the heel and forefoot of the shoe = a flat shoe.  The 12 mm of cushioning provides sufficient protection from debris and rocks without taking away the ability to "feel" the ground.  Merrell also designed the shoe in such a way that runners could go sockless if they so desired.....they fit like a glove.  If you decide to go sockless, please make sure you wash them occasionally for your family's and friends' sakes!  Those runners currently wearing Vibrams will be happy to know that the forefoot of the Trail Glove is splayed to accommodate the toes.  This feature allows the runner to push-off the ground just as if he was running barefoot on a grass field.  Overall, the Trail Glove appears to be the first actual "shoe" that embodies the principles of Vibrams without the hippy flare.  A great minimalist shoe for any off-road surface!

Check them out, and let me know what you think!
 http://www.merrell.com/US/en-US/Product.mvc.aspx/22875M/50390/Mens/Barefoot-Trail-Glove