Huarache hokum

I am naturally fairly sceptical, and so I have followed form with regards to the claims about barefoot running, or the rise of Huarache hokum as I'll label it here in a good humoured manner. I've been particularly sceptical about:

(1) claims about how bad trainers are for you, with some book authors seeming to claim that about 80% of the running population are at any one time injured as a direct consequence of wearing trainers. Eh? Where on earth does that figure come from? This sounds very suspicious and anecdotal. What is being counted as an injury? How was the data gathered?

There appear to be 2 key review papers in the scientific literature about incidence of running injuries - Richards et al 2009 and van Mechelen (1992) (not available online - too old I guess). Note however none have found evidence of the cause of running injuries as being the use of trainers, and none have done so experimentally.

So, the evidence is not anywhere near being robust at the present time. What is clear is that the forces experienced by runners differ in where they are exerted and their magnitude, depending on footstrike (heel based as with trainers, or mid- or fore-foot based as with barefoot) - see Lieberman et al 2010. So there is the potential for there to be differences in both type of injury, and injury incidence rates between barefoot and trainer wearing running, but the difference or cause of difference is not yet established.

(2) taking the stance that it is reasonable to compare incidence of injuries between lifelong barefoot running and largely sedentary western populations

Huarache Indians I assume run from a very early age, have a lifestyle which is not dominated by sedentary activities and are therefore well adapted physically to not wearing trainers. Most westerners who run probably take up running relatively late in life (i.e. post 18) and live largely sedentary lives. They have not grown up with the motion of running and consequently have not physically adapted to the same extent.

To then think about comparing the levels of running induced injuries between the two populations just seems crazy. It wouldn't be surprising if Huarache Indians were injured less from running, but not because of running barefoot, simply because they've been doing it for most of their lives.

A more valid, and interesting comparison, would be to compare injury rates between Huarache Indians (or other lifelong barefoot runners like some Kenyans), and any population of trainer wearing runners who had been running for the same length of time (so you control for extent of physical adaptation). I suspect you'd also need to control for biomechanic characteristics to ensure that the two groups were equivalent in terms of propensities to pronate etc.

So what is my position?

It is certainly worthwhile trying to establish whether there is a link between the use of trainers and incidence, type and severity of injury in running. No argument there.

If one found that there was a link, what would be the advice? Everyone to go barefoot? I suspect this would lead to injury too, partly as folk adapt to the new style and different stresses and strains are placed on the body. I do wonder whether even after adaptation to the new style that injury rates, types and severities would be reduced if everyone now with trainers went barefoot? I have a suspicion that the distribution of biomechanical characteristics might play an important mediating role. Are all Huaraches biomechanically neutral or is the incidence of pronation the same in western and lifelong barefoot running populations? Characterising this would be important before issuing general guidance on the appropriateness of running - whether barefoot or with trainers. Having said that, review evidence would suggest that the use of long distance, pronation control trainers has no effect on injury prevention (Richards et al 2009).

As ever however I am open to good quality evidence so my intention with this post is to encourage responses which might alert me to evidence I am missing. Comment away you barefoot runners, I remain to be convinced! :-)))