So, How Many Hats Do You Wear?

My photo
Pensacola, Florida, United States
Husband. *Dog Dad.* Instructional Systems Specialist. Runner. (Swim-challenged) Triathlete (on hiatus). USATF LDR Surveyor. USAT (Elite Rules) CRO/2, NTO/1. RRCA Rep., FL (North). Observer Of The Human Condition.

Thursday, January 28, 2010

To Bear The Brunt Of The Barefoot Run...

...we're talking something akin to Shakespeare's sound & fury here, folks.
Everywhere I turn, during every run I take with other runners, someone talks about either the barefoot running or the minimalist shoe mania. I'm certain using the term mania is accurate, because the proponents, even the ones who have minimal knowledge of biomechanics or sports performance, are all in a barely-controlled lather. Naturally, when a National Public Radio news program comes out with the results of a research article published in the journal Nature, that's when you know the manic have turned mainstream.
Daniel E. Lieberman, an evolutionary biologist, & others looked at the foot strike patterns of runners who wore shoes, & compared them to the patterns of runners who did not. Since our ancestors didn't have K-Swiss K-Onas, or Nike Frees, or Newtons, or even Asics Speedstars, it's safe to presume they were better built to deal with traveling the world (whether at high or low speed) barefoot. Here's the abstract from Nature:
'Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels & little cushioning relative to modern running shoes. We wondered how runners coped with the impact caused by the foot colliding with the ground before the invention of the modern shoe. Here we show that habitually barefoot endurance runners often land on the forefoot (forefoot strike) before bringing down the heel, but they sometimes land with a flat foot (midfoot strike) or, less often, on the heel (rearfoot strike). In contrast, habitually shod runners mostly rear-foot strike, facilitated by the elevated & cushioned heel of the modern running shoe. Kinematic & kinetic analyses show that even on hard surfaces, barefoot runners who forefoot strike generate smaller collision forces than shod rearfoot strikers. This difference results primarily from a more plantarflexed foot at landing & more ankle compliance during impact, decreasing the effective mass of the body that collides with the ground. Forefoot & midfoot strike gaits were probably more common when humans ran barefoot or in minimal shoes, & may protect the feet & lower limbs from some of the impact-related injuries now experienced by a high percentage of runners.'
You've heard of driveway moments if you've listened to NPR long enough. Those are the moments when a report is so good you sit in the driveway & don't get out of the car until the report is done. Well, I nearly had a Tourette's Syndrome moment; I was still several miles from the house & grateful my windows were rolled up so nobody could hear me curse.
First - if your study is funded by a company which makes minimalist shoes (Vibram, to be exact!) you're not going to bite the hand that feeds you (or, your lab assistants; Lieberman says he received no personal income from the company). We also know the dictum of research universities: publish or perish. If someone's going to pay for research I can publish, so much the better.
Second - while Lieberman states he is a marathoner, the NPR interviewer does not tell us whether he is a three-hour guy or a five-hour guy. Yes, there is a difference between the running style of faster runners & the less fast ones. A person who is walking will naturally strike first near the heel & then roll forward onto the ball of the foot. Slower runners & joggers also tend to do the same, as a natural extension of the walking gait. As the speed of the run increases, the runner tends to do either one of two things:
They pound the heels into the ground because they're overstriding (a result of experience in sprint-focused sports such as football, basketball and baseball), which causes shock-related stress & the injuries which result, or...
They adapt; shortening the stride & strike closer to the midfoot or the forefoot.
Third - the report was not an injury study, & Lieberman has no hard science to support his theory. Besides, my shoeless ancestors weren't running on Gonzales Street in the East Pensacola Heights, which is a slab of concrete. It is more likely they were running & walking on grass or dirt trails, which meant they had a better surface in the first place on which to run.
So, before you go throwing those running shoes into the rubbish, follow the money behind the research. Take a closer look at your stride mechanics. You can't, & probably shouldn't change, but a small part of your running mechanics. There are little tweaks you can do, but beyond a certain point there is the risk of serious injuries which can make you Once A Runner. If you decide to try a minimalist shoe work into them gradually (once again, the ten percent rule of thumb!) to see whether your muscles, tendons, ligaments & bones can handle the change.

No comments: