Wednesday, March 23, 2011

The Minimalist Shoe Dilemma

So you were "born to run", like the "idea of minimalism", want to "run free"...the way mother nature intended us to, or maybe you just had to have those minimalist running shoes because they came in that awesome color combination, etc.

If you say..."yup, that's me" (yes there are many of us out there), there's a good chance you've noticed an increase in aches and pains, probably an increase in injuries, maybe you've even given up on minimalist running shoes or even running all together. Maybe you haven't taken the plunge into this "brave new world" of running, but are interested in trying.


Regardless of where you shake out on the topic there are a few important pieces of information we should all know before we start in order to be successful. Here's the 500 lb gorilla standing there in the corner is this...The IDEA of running in minimalist shoes is more pleasing then the REALITY you may be left with if not transitioned to properly. And even then its not for everybody.

I'll begin the "what should I know" with a small piece of my own journey. I have watched the explosion of the "minimalist" movement over the last 2 years and have heard the passionate testimony of folks falling on both sides of the aisle (minimalist is the way to go OR it's for the birds). The debate continues, however that debate has given rise to some very good new research on running mechanics and injury.

Up until very recently, I myself have continued running in the same old shoes I have run in for years. For me (this is my opinion, but know it is strongly supported by lots of research), drum roll please...here comes the big secret, it's not about the shoes! It's about developing proper mechanics which is done through proper practice and by building the necessary tissue strength (stability), flexibility and endurance along with a whole host of other factors. Most of us know this, but most of us are also too impatient to take the time to do it properly.

So before we can begin to understand how we need to adapt our bodies to a minimal shoe we need to first understand what a minimal shoe really is. A minimalist shoe 1)has less cushioning and therefore lower to the ground as compared to traditional shoes, 2)has a smaller heel-to-forefoot differential a.k.a. "drop" (i'll explain this a little more soon). 3) and tend to be much lighter.


These are a few of my current running shoes NB 769, NB 904, NB 101(all New Balance - not meant to be an endorsement, just what I gravitate towards), non of which are by definition a true minimalist shoe. I am still working on the transition to a true minimal shoe like the New Balance Minimus Trail or Road.


Beyond minimal shoes like the New Balance Road and Trail there are the ultra minimal shoes, like the Altra Running Adam shoe pictured here.


Here's how these shoes compare:


Alright, so let's see why the considerations of cushioning and drop are particularly important.

Typically running shoes have a great big sole of soft cushy material that allows the end user to slam the heel of the foot into the ground during heel strike which sends shock waves up the leg into the spine with forces typically peaking around 4-6 times body weight (for a 175 lb man we're talking about 1,050 lbs of force). If the same form was maintained in a shoe with less cushioning I think we all know we wouldn't be running very much longer. On the opposite end of the spectrum, during toe-off, all that cushioning actually inhibits toe extension. Over time this can result in limitations in toe flexibility. When transitioning to a minimal shoe many of us realize that we must give up our old heel strike for a more friendly mid-foot striking pattern however fail to realize how much stress will be placed on the toes during toe-off as the toes are now forced to fully extend. This can often lead metatarsalgia (toe pain) and stress fracture just to name a few. The toes can be conditioned to withstand this stress, but it takes proper instruction along with some time and patience.


Drop, the simple way to say "heel-to-forefoot differential" is just a way to describe the difference in height between the heel and forefoot of the shoe. A greater drop means the ankle is positioned into more plantar flexion (point the toes down) while less drop translates to a more dorsiflexed ankle (pull the toes toward the shin). What does this mean functionally? In traditional running shoes our ankles are positioned in plantar flexion with the achillies placed in a shortened position. When transitioning to a shoe with a decreased drop too quickly achillies tendonitis is a common outcome. Here's an example of what various drop distances (measured in millimeters) can look like:


The picture above demonstrates the differences between how a foot would be positioned in a 0 millimeter (mm) drop shoe, 10 mm drop shoe and finally a 16 mm drop shoe. In the the 16 mm drop shoe the ankle is positioned in about 10 degrees of plantar flexion vs about 5 degrees in the 10mm drop shoe vs 0 degrees in the 0mm drop shoe.

So here's the bottom line: Having run in traditional running shoes throughout your life (raised heel with lot's of cushioning), its very likely that the muscles in your feet, ankles, knees, hips and core are not conditioned properly to wean yourself off these shoes cold turkey. If you begin running all your mileage in a minimal shoe you are likely to experience aches, pains and injury. Studies in tissue mechanics have shown it takes 6-8 weeks to see changes in strength and in some cases 10-12 weeks to see increases in flexibility. So to transition properly takes some commitment, but it can be done.

If you have questions, you have resources at your finger tips...literally. Whether you need advice on how to make the transition, need input on what exercises to perform or are coming back from an injury and need some video analysis to pick apart your current mechanics I'd be happy to play a part. Leave a comment or reach out to me directly at jbagley@pro-activity.com

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