I follow the running blog Runblogger by Pete Larson. His most recent post (see it here: http://www.runblogger.com/2011/07/criteria-for-safe-transition-to.html?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+Runblogger+%28Runblogger%29) is about physical therapist Jay Dicharry and his criteria for transitioning into a minimalist or barefoot-style shoe. Dicharry is director of the Speed Lab at the University of Virginia and, as he has tons of experience treating runners and has conducted much research, is an expert in the field of running gait and injuries. Pete summarizes Dicharry's three criteria for the transition in his post and directs you to Dicharry's blog for a full explanation.
As Dicharry explains it, the switch from a "regular" shoe to a more minimalist shoe can be significant... without all the cushioning and the lower heel, your foot will "feel" the ground more, which by the way, is a good thing--your foot and ankle were designed to do this and take more of the shock so that the knee and hip are less impacted. Wearing shoes all our lives weakens our feet, they don't have to do what they were meant to do. Dicharry has found over the course of treating many, many runners, that certain criteria need to be met before successful transitioning can occur.
Dicharry's three criteria are:
1. Mobility - Two things here: You need to be able to dorsiflex your foot toward your shin up about 25 degrees. This requires your Achilles to be flexible and if it isn't, you will need to do some calf stretching to get it to that point before you try the transition. You also need to be able to dorsiflex your big toe about 30 degrees up while your angle is at about 5 degrees toward your shin. This allows you to roll over your toes instead of your forefoot as you run.
2. Single-leg Standing Balance - Standing on one leg with foot flat on the floor, you need to be able to balance for 30 seconds with your upper body still. Dicharry points out that, as the midstance running phase is this "single-leg squat," and that the foot needs to be "pro-active not re-active." This is called proprioception--your perceived sense of where your body is and what its doing.
3. Ability to Isolate the Flexor Hallucis Brevis (big toe flexor) - Stand on both feet and see if you can drive the big toe of one foot into the ground while slightly raising the rest of your toes, keeping your ankle in place. Do not curl your big toe. Then reverse it--drive your other toes into the ground while lifting your big toe. Dicharry explains that one of the ways we differ from other primates is that we have a longitudinal arch, which helps us run.
If you're weak in any of these areas, Dicharry recommends practicing these movements to strengthen and stretch those components before beginning a transition into minimalist or barefoot running. If it's mobility that gives you problems, he recommends a 10 to 12-week stretching program. For balance, improvement comes quickly, in about two weeks, if you practice a lot. And strengthening your foot muscles will take about six to eight weeks. Of course, if you can already perform these three tests with no problem, you're good to go!
To read the original post by Jay Dicharry see: http://uvaendurosport.wordpress.com/2011/07/09/less-from-your-shoes-more-from-your-feet/)