A few weeks back I was talking on the phone with Jay Dicharry, a physical therapist and director of the Speed Lab at the University of Virginia. Jay is one of the most knowledgeable guys I know when it comes to questions about running gait and running injuries, probably because he combines a strong research background with a wealth of applied clinical experience treating injured runners. It doesn’t hurt that he also has at his disposal one of the most sophisticated gait labs in the world.
One of the questions I asked Jay while we were talking was whether he had any specific criteria that he felt were important in ensuring that a runner can make a safe transition into more minimalist, or barefoot-style running shoes. Jay indicated to me that there are three specific things that his clinic looks for before progressing someone into more minimal footwear or barefoot running. I’m going to give the short form of his answer here, then direct you to a blog post that Jay recently wrote that explains these things in much more detail.
1. You have to be able to isolate and control the flexor hallucis brevis, a muscle in the foot that flexes the big toe and helps to actively stabilize the medial arch (the photo at the top of this post shows this little muscle in action).
2. You have to have sufficient length in your Achilles tendon and plantar fascia. What that means is you have to be able to dorsiflex the ankle (tilt your foot up toward your shin) to 20-25 degrees, and you have to have 30 degrees of dorsiflexion in the big toe when the ankle is very slightly dorsiflexed so that you can roll over the toes during stance phase of the gait cycle.
3. You have to have good single leg balance, which is basically keeping the medial and lateral borders of the foot in contact with the ground for thirty seconds with your eyes closed. If you can do that, you’ve got a good amount of internal control to stabilize the foot and don’t need a lot of help from a shoe.
For more detail on each of these 3 criteria (with pictures), see Jay’s full post on the UVA Athlete’s Body Blog.
Jay indicated to me that they have been very successful using these criteria so far. In fact, he said that he hasn’t had anybody who has been evaluated under these rules have problems after starting either minimal or barefoot. In his excellent post, Jay also discusses how one might work to improve limitations if one of these tests is not passed – in a nutshell, stretching and strengthening work are critical. Again, his post on transitioning can be found here: http://uvaendurosport.wordpress.com/2011/07/09/less-from-your-shoes-more-from-your-feet/
I’ll finish here with a challenge. After Jay related these criteria to me I was curious to see if I could pass his one-foot balance test. I grabbed my wife and we took turns standing on one foot with our eyes closed. Now my wife is a long-time practitioner of yoga, so she spends a lot of time stretching and balancing, but I also know that she has a weakness that might give me an edge. She has a monstrous bunion on her right foot, and her big toe points inward at an almost 45 degree angle (she has had this as long as she can remember back to childhood, and I’d love to know if it was congenital). If she was going to fail, it would be on this foot because she can’t use her big toe on that side to effectively stabilize herself. Sure enough, I managed the full thirty seconds on each foot with my eyes closed. She did just fine on her left side, but while standing on her right foot, she flailed around and had to put her other foot down after a matter of seconds. That little test really cemented for me the importance of proper stabilizing function of the big toe.
Anyway, I encourage you to give the balance test a try – it’s not as easy as it might seem. If you do try it, leave a comment and let me know how it went!
Update 7/15/2011: Jay Dicharry just posted a follow up with more details on balance and proprioception for runners. You can read it here: http://uvaendurosport.wordpress.com/2011/07/14/proprio-what-a-deeper-look-at-balance-and-stability/.