More on minimalist shoes (from our forum)

See this on our forum...
I've had an interesting couple of weeks of running. I have been running really comfortably in my New Balance MT101s. They are a cross-country minimalist shoe, so no gradient from heel to toe, and very little cushioning. Over the last year, I've run mostly in the trails with these shoes, but now that I'm preparing for an ultra distance run that includes cobblestone and rock, I've begun running on the road with these also.
Well, I got a little nervous a month ago, that I could not sustain the very long distance in these minimalist shoes. I started researching every shoe on the market, looking for something with a very flexible sole to match what I'm running in, but with more squish. NB is coming out with one late March, but that is too close to my race date. In the meantime, I bought a Brooks Pure Flow. They feel like slippers, and the sole is really bendy. I've done two three longer runs in them, and the knee pain raised it's ugly head. I've blamed it on skiing, weight in my pack, inconsistent downhill running, knee alignment in my cycling cleats. During my latest run, it was really obvious that it was MUCH more work running in these shoes than my NB 101s. I can feel my feet fighting for balance on the landing, and having to move through a greater range for push off. I can feel myself heel planting, despite my best efforts, and then the squish allows my heel to go lower than my toes, so adding stretch to the achilles.
Today I did a recover run on the treadmill in my good old NB 101s, that I've been running in for a couple of years. My knees felt GREAT. So yes, I'm still a little nervous about running really far over cobblestones without much under my feet, but I can see that the squishy shoe is not my answer.
My observations fit really well with the article below.
Ginny

What Can We Learn from Watching Children Run?
By Irene Davis, PhD, PT, FACSM, FAPTA, FASB
It has been suggested that running is naturally innate in us as it was a means of survival. Natural running can be defined as running in the way we were designed for. This can be best observed when one is running without the interference of shoes or braces. Observing the gait of a child,who has not habituated into shoes, provides a window into the development of natural gait. When a child first walks in a pair of supportive shoes, after toddling around barefoot, it is very unnatural and awkward. This is not surprising, as their shoes have disrupted the natural inertial characteristics of their leg. In addition, shoes have added unnatural lever arms of the ground reaction force, increasing external moments thatchildren now need to control.
When children first learn to run, they naturally land on their forefoot with a relatively flat foot pattern (6). Bythe time they are four years old, and likely habitually shod, they have adopted a rearfoot strike pattern when they run. A habitually barefoot runner will also strike the ground with a fairly horizontal foot. They land on the lateral ball of the foot, with the heel slightly off the ground. The heel then lowers to the ground in a foot-flat position and the foot then plantarflexes for pushoff.
Habitual barefoot runners do not land on their heel for the very reason that it hurts. If running were essential to our survival, then it makes no evolutionary sense that we would run in a way that is painful. The pain associated with a barefoot heelstrike is related to the high impact transient that is associated with a rearfoot strike pattern. This very quick rise to peak in the vertical ground reaction force curve results in a high rate of loading experienced by the body.
The body is comprised of viscoelastic structures, which are sensitive to rates ofloading. If these loading rates are high, these structures may not have time to adapt to the load.This can result in pain and, with time, injury. Heelstriking in modern cushioned running shoes is not painful; in fact, it is comfortable. However,the impact transient is still very present. This impact transient has been associated with a varietyof running-related injuries both retrospectively and prospectively (18,11,12,3).
Running barefoot, or in shoes that do not make it comfortable to land on one’s heel, results in a more anterior strike pattern. This strike pattern is seldom associatedwith an impact transient (8,17) and thus is likely to reduce injury risk.
There are other reasons to consider running barefoot or in minimal footwear. No one would argue with the fact that a strong foot is more likely to be a healthy foot that is more resistant to injury. It has been shown that when individuals remove their shoes and go barefoot, or run with shoes without any arch or rearfoot support, their feet become stronger (13,2).
Our feet are remarkable structures with 26 bones, 33 joints,and 30 muscles. They were designed for all of the locomotor demands of our ancestors, including running. The arch itself has four layers of muscles, which are critical to controlling the deformation of the arch as we load it. These muscles are the first line of defense for the plantar fascia, which lies directly below these muscles.If those muscles are unable to adequately control the lowering of the arch, the plantar fascia becomes excessively strained. With enough repeated loading, plantar fasciitis ensues. It is, therefore, not surprising that plantar fasciitis is the most common foot injury that clinicianstreat.
With increasingly supportive footwear, we have conditioned our feet to be lazy.We are often misled into believing that cushioned running shoes soften our landings. Theydo indeed make it more comfortable to land on our heels; however, there is evidence that demonstrates we adjust our leg spring to the surfaces we land on. For example, a study by Bishop et al (1) revealed that knee stiffness was significantly increased when landing in a highly cushionedrunning shoe, compared with a low cushioned shoe or in bare feet. Knee stiffness has been associated with greater rates of loading duringlanding (10).
While it may seem counterintuitive that you land harder in softer shoes, this relationship between landing behavior and surface hardness is well supported by other research, as well (9,4,5). We highly underappreciate that our feet areremarkable sensate organs. There is a wealth of sensory input from our feet that is critical tonormal function. These sensory signals provide important information that assists with balance and stability. It has been shown that even a thin pair of socks negatively influences static standing balance (15). Wearing socks on your feet while you perform functional activities is not much different than wearing gloves on your hands during daily activities. Our recent research on single leg landings has demonstrated that dynamic stability is also significantly decreased in standard running shoes compared with bare feet (14).
Modern running shoes with elevated cushioned heels, arch support, and stiff heel counters interfere with the natural movement of the foot. Shoes were originally designed to simply protect the bottom of our feet, not replace foot function(16). Seldom are we successful at improving on nature. Therefore, the move towards more minimal footwear that has no cushioning or support is very encouraging.
While there is much to learn from watching children develop, perhaps there is even more to gain from studying those who have grown up barefoot. If children grow up never wearing shoes, they mature into forefoot strikers when they run (. However, if they grow up wearing modern running shoes, most (75%) mature into rearfoot strikers when they run (7).
We cannot disregard that one significant difference is the shoes. For those who have been habitually shod in modern cushioned and supportive running shoes, a slow transition to barefoot or minimal footwear is requisite. However, this patience will pay off with stronger feet and reduced impacts experienced by the body. For those runners with intact neuromuscular systems seeking a stronger, healthier foot and more natural running pattern,less will truly be more.

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