Unfortunately they didn’t record much kinematic data beyond stance time, but they speculated that the two subjects with no impact transient were midfoot strikers and the others heel-toe. So yes, I suppose form manipulation could change things – it would be interesting to see how those two very divergent individuals would respond if they ran barefoot.

As always, a really nice article, Pete. One thought,
tangential to your main point but here… The impact peak is indeed just the
weight of the foot hitting the ground. If you were to model the body mass on
top of a spring (a leg) you would see something that looks just like the active
peak without the impact. But if you add to that model a small weight at the
bottom of the spring, you would see something that looks much like an impact force
preceding the active peak. The important thing with respect to injury, is what occurs
at the tip of the active peak – that is where joint torques and forces are
greatest and relate to where injuries (like osteoarthritis) occur. 

 This is why I will follow your blog for as long you keep it.  You always provide great explanation and insight and I agree with everything you just stated.  I agree that because of a lack of natural selection for our physical traits that their will be greater variability but also it would be unlikely that multiple forms would ever arise like the finches.   

I am curious about the heel strikers of the Kenyan children as Ii reminds me about the picture you put up with the Patrick Makau heel striking in his world record race.  I often hear people talk about elites running a certain way but does that mean the way they run is the best or even the best for them.  Is it possible that Makau could have ran even faster if he didn’t heel strike?  Was he running the most efficient way possible?  Are the Kenyan children that heel strike, running the most efficient  way for them? Just because they have never had shoes on their feet, does that mean they naturally run the most efficient way?    

CULTURE ON THE GROUND: the World Perceived Through the Feet
TIM INGOLD 2004

available here:
http://www.nyu.edu/classes/bkg…

It explores the role hand-tools vs feet-walking/locomotion played in evolution…it goes on to some cross-cultural analysis of walking gaits, among other things…the develop of distinctive ‘form cultures’

We’re anti-establishment and not entirely minimal, so there’s something for all y’all. ; )

Bob,

1. I agree to an extent, but I think it’s the combination of both “hard” and “unvarying” that is at issue, and perhaps moreso the latter than the former. I can run fine barefoot on asphalt, in fact I find it quite enjoyable, and most barefoot runners would agree that smooth asphalt is the preferred surface to run on.

2. I’d guess something along the lines of a shuffle run with minimal flight time? That being said, I’m pretty sure my grandmother’s severely arthritic knees would prevent her from doing even that!

So our heels make it clear that evolution has designed us to walk rather than run, so all the talk about the “natural” way to run sort of becomes moot: even though we can run, it’s not our primary evolutionary design.

Thanks Theo – all great questions, and I wish I had the answers! Makau is wearing the Adidas Adios I believe, which has a pretty traditional offset for a road flat – would be very interesting to see him run barefoot or in something flatter just to see what would happen. Likelihood of that is low of course given his sponsorship, but Adidas is making a new, lower profile flat called the Hagio and it will be interesting to see it on the feet of some elites. These kind of questions are what keep me going.

Those four species/genera of finches would not exist if intraspecific variation did not exist in the population(s) that gave rise to them. We humans deal not only with intraspecific variation due to our genetics, but also a huge amount due to environmental causes like past/current shoe use and activity levels. In that sense we are quite different than a typical wild population. For a woman who spends 60 hours per week in high heeled shoes and is not going to change that habit(yes, they do exist and have been studied), a 12mm heel lift is probably quite reasonable.

What does ‘natural’ running form mean, considering the abundance of ‘artificially monotonous surfaces’? (e.g. roads, golf courses, exercise trails).

Human variability + surface variability -> form+surface homogeneity