Monday, March 1, 2010

The Case of the Vanishing Achilles Pain

I have continued with my barefoot treadmill experiments and have stumbled upon a completely unexpected side effect.  I first noticed it after I moved from being very cautious and slowly jogging to getting in to an actual run.  The morning after I did my first real "run" (and by that I mean the treadmill was at least fast enough that walking was impossible at that speed) without shoes I woke up and immediately realized that I had zero aches in my achilles.  I brushed it aside though as a fluke and went about my day.  That night I once again did twenty minutes unshod on the treadmill.  Again, the next morning I had absolutely no discomfort in my achilles.  At all.  Nothing.

All day long I kept walking funny trying to stretch them out and prove that they still hurt.  They always hurt the morning after a run, no exceptions.  But they kept on feeling great!

Since this initial discovery I have been hyper-attentive to it.  Friday I did a long run and sure enough, the next morning my achilles were achy and creaky.  Sunday I did some more barefooting and again this morning I had no aches at all (in my achilles; barefoot running so far has not had the same magic power over my knees which have been slightly cranky).

So it has got me to wondering exactly what is going on and why this is happening.  During the barefoot runs I often feel some discomfort and tightness in my achilles but that doesn't seem to translate into soreness the next day.  In fact it actually seems to help reverse the problem and leaves me feeling better.

I'm just beginning to try and figure out what is going on but I have to believe that it has something to do with the mechanics of it all and how my stride is affected by wearing shoes.  Harvard has done studies that lay out the differences between heel and forefoot striking and the forces incurred with both.  It has lots of pictures and videos so even an idiot such as myself can learn something.  They compare heel striking to dropping a beam on its end; it comes to a sudden stop with the lower leg absorbing most of the force.  Changing to a more forefoot strike and the vertical momentum is converted into rotational momentum and reduces the load on the leg.  This could account for why I feel so much better afterwards, the strain on my achilles is significantly reduced.  I find it much easier to keep off my heels when I'm not wearing shoes because there is no built-up heel to get in my way so this could be a factor.

Or maybe it as something to do with the treadmill and how I run on that.  Or that I have been running much more conservatively.  I'll just have to keep trying new things and increasing the time and speed to see what happens.


  1. that is really interesting. Although I totally believe that BF running reduces mechanical load on the joints, I'm surprised it felt easier on the achilles! I'm feeling a bit disloyal to my own minimalist experiments at the moment, since I'm not so much for the running indoors, and it's been, you know, winter outside. Am definitely looking forward to some nice weather where I can stretch my toes.

  2. Hmm..I have read that BF running can be good as well and I experimented a teeny bit this November on the beaches of Aruba. I did not feel any pain after and ran a total of 2 miles.

    Some think that our running shoes are over engineered and cause problems. BF running could be just the medicine you need.

    My other thought is that since there is no built-up heel in the way of your drop you could be stretching your achilles further than normal thus loosening it and making it feel better.