Wednesday, May 27, 2015

It's gotta be the shoes

It starts with these articles

http://fittish.deadspin.com/vibram-fivefingers-still-stupid-now-culpable-1572955736

These people pour their scorn and derision out because they don't like or don't believe in a certain type of footwear.  I don't get it.  You like your Nike shoes, wear 'em.  But, I'm getting ahead of myself.

For those who don't know, let me introduce myself.  My name is Eric Gaden R.N.  Yes, I am going to use that.  I have 7 years experience working in the emergency room and as an ER nurse, I believe I have a better than average grasp of human anatomy and physiology.  I have seen all types of injuries and wounds caused by running and other things.  I have not done any specific research or experimentation on this subject because no one will pay me to and I like living indoors.  Even if someone would pay me, I probably wouldn't do it because I wear 5 fingers for running and would be considered biased.

Yep, I wear those funny toe shoes for running.

I have detailed some of my experiences with them on my blog.  I have run a road half marathon and a trail full marathon in them.  I do the overwhelming majority of my running on roads and hard surfaces. Before I started with them I ran in Mizuno.  Good shoes.  Another disclaimer.  I read Born To Run.  But I read it 2 years after I started wearing Five Fingers.  I don't think the running feats mentioned in the book are expressly related to footwear so much as lifestyle

Let me address some of the claims made in the above mentioned article and say something about the lawsuit.


So, Vibram made the claim that their shoes could "Reduce foot injuries and strengthen foot muscles.".

Let's take a look at that.  What the modern running shoe was doing, prior to the minimalist movement, was protecting the foot.  They made claims that protecting from over pronation would reduce injury rates and improve your running.  This has been proven not to be as reliable as it was once thought.

http://www.sciencedaily.com/releases/2013/06/130614100821.htm

http://www.runnersworld.com/running-shoes/does-pronation-matter

Certainly there is enough research to disprove many of the advertising claims made by motion control shoe makers and instigate a lawsuit.  However, it is harder to sue an entire industry.  Vibram stepped out and did something different.  This makes them an easier target.

Let's also take a look at the negative effect mentioned in the article.

"This study showed that increases in bone marrow edema [the precursor to a stress fracture] are more common in subjects who were transitioning to the [Vibram FiveFingers],"

That makes total sense.  The body only changes in response to stress.  You stress your muscles to make them stronger.  You stress your cardiorespiratory system to make is better.  In this case, you are stressing your bones.  The problem is they are quite a bit slower to change.

http://en.wikipedia.org/wiki/Bone_remodeling_period

Your soft tissue changes much faster. Lungs cells replace around every 6 weeks, intestinal lining cells can change every 4-5 days.  Muscles can adapt very quickly too.

http://www.unm.edu/~lkravitz/Article%20folder/musclesgrowLK.html

Bones don't.

Now, take the built up running shoe.  It protects your foot from the flex and stress that would cause muscle and bone change.  You take a cast off an arm and the arm below is withered and atrophied because you have reduced the stress on the whole to remove the stress on a part.  An overbuilt running shoe will reduce stress on the whole foot.

Take away that protection and it increases the stress.  Increase the stress and it will get stronger.  This isn't new knowledge.  Move too fast and you overstress a weakened structure and you get injuries. Keep up the stress and you get a stronger, more durable foot.  A stronger, more durable foot leads to stronger muscles and less injuries.  The theory is sound.

But... and there is a but.

For a period you would be at a higher risk for injuries, especially bony ones.  Had you never put your foot into the overly protective shoe, you would be better off, theoretically.  But most of us have.  So we increase our short term risk of injury to decrease our long term injury and increase our long term foot strength.

That bone marrow edema is the body's initial response to increased stress.  If you hurt too much, slow down your transition, back off your pace or your mileage.  Or wear the big shoes, if that is what you like.  I suspect the injuries are more related to training too much, too soon, too hard.  Anyone know a runner who would do that?

So, in conclusion, if you like built up running shoes, wear them.  If you like minimalist, wear them.  There are advantages and disadvantages to both.  I think the short term slow down in pace is fine, I'm not that fast anyway.  I think that, over the long term, I will have stronger, less injury prone feet and legs.

You don't, that's fine.  This lawsuit isn't about the science behind the shoe, it is about advertising.

And don't call me a sucker.