Wednesday, February 9, 2011

Finally: Real Foot-Strike Data!

The infamous Runblogger (AKA Peter Larson, PhD) has written some great posts over the past few days about a recent conference on running injuries he attended as an invited panelist.

His posts contain lots of great links, among them links to two posts from the Center for Endurance Sport at the University of Virginia with some hard data about rates of foot force loading:
  1. http://uvaendurosport.wordpress.com/2011/02/07/loading-rate-part-1-what-does-it-mean-for-you/
  2. http://uvaendurosport.wordpress.com/2011/02/08/loading-rate-part-2-forefoot-midfoot-rearfoot%e2%80%a6%e2%80%a6-who-cares/
The conclusions take some of the hot air out of the 'best foot strike' arguments.  Basically, there is no 'compelling' evidence that there is a single all-around 'best' foot strike for all humans:  The 'best' foot strike varies with the individual.  Conversely, you can have problems with force loading no matter which foot strike you use.  Fortunately, the same general remedies apply, independent of foot strike.

The same cannot be said for running shoes:  There is growing evidence that "Less is More" when it comes to shoes.  Changing to a lighter, less structural shoe can reveal latent problems with your stride, which provides the opportunity to improve efficiency and performance while simultaneously reducing the risk of injury.  The underling issue seems to be that the foam and structural elements in heavy running shoes serve to reduce the loading force seen by the foot: Removing that material makes it clear how your stride is actually performing.

This even applies when taken all the way to no shoe at all:  There is also some evidence that those who learn to run well barefoot have fewer problems when they run in shoes, compared to those who don't run barefoot at all.  That is to say, barefoot running may teach skills that are useful when running in shoes.

Here's my take-away question:  Let's say you learn to run barefoot and thoroughly address all stride issues, then you start running in a heavy structural shoe that works well with your new stride (assuming such a shoe exists).  Could this be the perfect combination for life-long minimum-impact running?  Take a proven 'clean' stride, then add as much cushioning as possible?

My own personal experience combined with the Magic 8-Ball says: "Seems Likely".  I suspect the full answer will involve ensuring that the heavy shoe does not add negative factors (such as weight, limited flexibility, and a higher heel) that could cause the stride to change.  I think you'd need to occasionally run barefoot to ensure your stride remains solid.

Interesting stuff.