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March 27, 2012
Do You Use Orthotics or Supportive Footwear? Why It May Be Time To Stop


The last century has seen a a gradual and progressive increase in the amount of supportive footwear available for everything from walking to running. Some have even made the claim that many of the joint and muscle problems associated with our modern lifestyles have everything to do with our footwear. That is true to a certain extent, however supportive footwear and orthopedic devices may have only made the problem worse, not better.

Humans and bipedal hominids have been running for millions of years, and of course for most of that time that humans have been on earth, we ran barefoot. Modern running shoes were actually only invented in the 1970s. Since that time, back, hip, knee and ankle overuse injuries, including tendonitis, and muscle disorders have only increased. So health experts came up with what they thought was a novel approach--namely that "we need more support from our footwear." Nothing could be further from the truth.

Biomechanics of the Foot Strike


Your feet are your connection to the ground. What that said, there’s a lot of prerequisites that go into performing your movements. One of the functions that the foot has that’s of particular interest is that it’s a base of support; whether it be in a single stance, as you would be if you’re sprinting, or in a double stance if you are walking, squatting, or other basics.

The second component to it is that it’s a mechanism for leverage to create propulsion. And for propulsion to occur: 1) There must be contact with the ground and it has to act as a base of support in order for that to happen. and; 2) The other component that the foot has or is responsible for is shock absorption. You cannot propel yourself and not be able to absorb the impact at contact. Those four functions that the foot has are all intertwined, so no one function is superior to the other. It’s the sum of all functions that creates a superior foot.

A typical sequence for foot function regardless of if you’re walking, if you’re jogging, if you’re running or sprinting, is that with your foot, the initial contact is with the outside of your heels first. The second step that occurs is what we call pronation; that’s where your foot starts to flatten, if you will. That mechanism there is essential because that is where a lot of force absorption, absorbing impact at contact occurs, but also too, its second function there is to set up the foot for the final phases of contact with the ground.

The third step after pronation is supination; this is where your arch starts to increase in height, which permits rigidity in the foot to allow you to toe-off, which is the final stage where your toe-off, in the true sense of the word, should occur between the first and second toe. Most people land on the heel and pronate but they pronate either too soon, too abruptly, or it’s sustained too long so that their foot is forced to rush into supination. In doing so, it’s almost like a flicking mechanism where you end up toeing-off on the outside of your foot.

Supportive Footwear and Orthotics May Be Your Source of Pain

Other support systems besides the foot itself will aggrevate this problem for many. When you remove the primary support system of the foot and use supportive devices instead, everything relating the lower body joints becomes weak. This includes the ankle, knee, hip and even lower back. It affects everything. What essentially occurs when you use supportive devices such as cushioned footwear and orthotics is that you interfere with the normal neural processing that is meant to occur between the point of impact and propulsion. This dramatically and detrimentally affects the natural development of the joints and their strength. If we compare the joint and muscle strength of feet and ankles of those in developed societies to those in underdeveloped societies such as in Africa, there is a substantial difference in the development of these joints and muscles.

For example, Kenyans can run barefoot and outrun most western endurance athletes with what are considered the best running shoes. The reverse scenario is impossible. In 1960, for example, a shoeless Abebe Bikila of Ethiopia won the 1960 Olympics marathon in record time. By not ‘heel-striking,’ barefoot runners avoid painful and potentially damaging impacts that concentrate the equivalent of two or three times one's body weight on to a coin-sized surface.

One of the problems with using performance footwear is that once they’re out of the support, they don’t necessarily use their foot correctly to initiate a lot of the basic movements, including walking for that matter. So they run into an issue where they don’t really use the foot and they’re more from-the-knee-up dominant versus athletes such as distance runners or recreational runners.

They have a tendency to just use the foot passively in the sense that it’s there just to make contact and you just are going through the motions with your legs. The foot actually has an integral part to a toe-off which most people won’t use. And sometimes shoe wear and potentially orthotics can actually hamper that dysfunction.

The whole scenario whether it be a weight belt, orthotics, or potentially certain types of footwear, is that our body is meant to respond to a stimulus, a change if you will, and that change or stimulus has a threshold for stimulating the body. Once you’ve reached that threshold, which in each person is a slightly different, the body decides to shut off because it knows that something else is doing the work and many times that’s where people run into problems. That dependence now becomes or supersedes a lot of what they’re doing in their training or daily lives. It becomes a crutch that does not address the root causes of dysfunction in gait, muscle strength ratios and other biomechanical deficits. The well-intentioned use of orthotics may actually backfire for a large percentage of the population.

Three-quarters of runners who wear shoes land squarely on their heels -- about 1,000 times for every mile run. But even well-cushioned sports shoes that help distribute weight across the foot cannot fully absorb the shock of these blows: consequently 30 to 75 per cent of regular runners each year suffer repetitive stress injuries.



By contrast, the vast majority of unshod runners don't hit the ground with their heels, landing instead on the sides or balls of their feet, the study found.

"People who don't wear shoes when they run have an astonishingly different strike," said Daniel Lieberman, a professor at Harvard University. "By landing on the middle or front of the foot, barefoot runners have almost no impact collision."

Lieberman and colleagues helped fill this void by studying the gaits of three groups of runners in the United States and Kenya: barefoot, shod, and those who had converted to shoeless running. "Most people today think that barefoot running is dangerous and hurts, but actually you can run barefoot on the world's hardest surfaces without the slightest discomfort and pain," the study found.

"All you need is a few calluses to avoid roughing up the skin of the foot." But making the switch to barefoot running is not simply a matter of kicking off one shoes, the authors caution.

Running unshod or in so-called "minimal shoes" requires the use of different muscle groups. "If you've been a heel-striker all your life, you have to transition slowly to build strength in calf and foot muscles," Lieberman said.

The study, published in the British science journal Nature , also bolsters evidence suggesting the human foot evolved for rapid upright motion, said William Lungers, a professor at Stony Brook University Medical Center in New York.

"Bipedalism" -- walking on two feet -- "has been around for millions of years, and we have been unshod for more than 99 per cent of that time," he wrote in a commentary, also in Nature. "Our endurance running abilities may have evolved to enable our ancestors to engage in 'persistence hunting'," the ability, in other words, to run down one's prey, he said.

In the future, he hopes, the kind of work done in this paper can not only investigate barefoot running, but can provide insight into how to better prevent the repetitive stress injuries that afflict a high percentage of runners today.

Ditch The Running Shoes and Orthotics?

Should you ditch your running shoes and orthotics altogether? While the results might seem to suggest that you should go barefoot -- a specific way of running that has recently become popular thanks to the best-selling book "Born to Run," by Christopher McDougall, in which the author argues that barefoot running is better for you.

Critics say that the problem with running sans shoes is that most of the man-made surfaces we run on are not "compliant" -- they don't give, or compress, at the right time to absorb the peak forces on your joints, Kerrigan said. "That's simply not true," said Morris Sonnen, an L.A. Doctor of Chiropractic. "If we look at just the last few thousand years, there were mostly developed roads with extremely hard surfaces and most of our ancestors wore sandals or shoes with extremely little or no support at all...how did they function on these man-made surfaces. Quite simply, they were stronger and they did walk and run on very hard surfaces," he added.

10 Myths of Barefoot Running

Barefoot running leads to stress fractures. Without a doubt, the most common concern with barefoot or minimalist running is the development of a stress fracture. While there have been documented cases of this in the literature, stress fractures occur as a result of a change in activity without gradual adaptation and are not directly related to the shoegear or lack thereof. We actually should see a decrease in the likelihood of stress fracture given the change in stride and cadence that one acquires while running barefoot.

We should see weaker bone trabecular patterns on those wearing cushioned running shoes due to decreased intrinsic muscle strength, resulting in a proportional decrease in the force acting on the respective bone.

I have flat feet and I need support. Lees and Klemerman have demonstrated that there is no correlation between foot type and running injuries, specifically with a pes planus deformity. During barefoot running, we avoid heel striking and land more on our forefoot or midfoot. Once the forefoot strikes the ground, pronation of the entire foot begins (not isolated pronation of the subtalar joint) and continues until the point where the heel touches the ground. Arch height becomes irrelevant as does the commonly described concept of pronation with the heel striking the ground first. With a forefoot/midfoot strike, pronation is very beneficial and helps to absorb shock.

I weigh too much. While this is a common excuse to not run, being overweight is not reason enough not to run barefoot or in a minimalist shoe. In 2010, Leiberman and co-workers were able to demonstrate that habitually unshod runners were able to generate smaller collision forces than shod heel strikers. In other words, by forefoot striking, we decrease the force that transmits through the lower extremity, thereby reducing torque forces to the ankle, knee and hip joints. Clearly, we can see that if people weigh 250 lbs, they would be placing more force through their joints by heel striking then by landing on their forefoot.

I have bad knees. Osteoarthritis of the knee is a common concern among many runners, especially older individuals who have run the majority of their lives. There are many theories as to why running is bad or even good for your knees. So many in fact that elliptical machines were invented to be used as a form of exercise similar to running without causing excess pressure to the joints. However, these elliptical machines do not reproduce anatomical motions and an in vivo force analysis reveals there is less force with walking than with an elliptical trainer.

We know that ground reactive forces are greater with heel strike in comparison to unshod or barefoot runners who adapt a more forefoot strike pattern. Numerous studies have demonstrated higher ground reactive forces and mechanical stresses to the knee while running in traditional running shoes as opposed to barefoot. A recent study published in the British Journal of Sports Medicine looked at patients with knee osteoarthritis over 12 months and found no difference between wearing a lateral wedge orthotic versus a control flat insert. Similarly, a systematic review of literature demonstrates that external knee adduction moment and pain associated with knee osteoarthritis is higher in individuals wearing sneakers in comparison to those who do barefoot walking.

How Do Orthotics And Plantar Fasciitis Come Into Play With Barefoot Running?

I can’t do barefoot running because I need to wear my orthotics. Orthotics have become more overutilized in the practice of podiatry then ever before. It is very common to see runners present with plantar fasciitis, a normal arch, cushioned running shoes and orthotics they have worn.  When running barefoot or in a minimalist shoe, we do not need to control motion at the rearfoot because heel striking is not occurring and “excessive pronation,” as described by Root, does not occur. While we have numerous studies that do not support the use of orthotics for running injuries alone, it becomes a challenge to convince the patient they are not needed.

I have plantar fasciitis so barefoot running would be too painful. This article was not intended to discuss the pathomechanics or treatment options of plantar fasciitis. However, we are anecdotally seeing resolution of symptoms in those who adopt this style of running. One potential explanation is the development in strength we see to the intrinsic musculature, specifically the abductor hallucis muscle, which is a primary supporter of the arch.

Another overlooked phenomenon is the fact that the majority of running shoes place your ankle into plantarflexion. This forces the body to compensate by increasing lumbar lordosis and increasing pressure to the heel as opposed to having more even distribution throughout the foot.

Addressing Other Perceptions About Barefoot Running

Barefoot running causes severe calluses. Calluses on our feet form as a result of shear force on the plantar surfaces of the skin that produces excess friction. Shear force that occurs in the horizontal plane is the key to understanding this concept. Direct pressure does not produce calluses or we would see a high preponderance of heel calluses in runners as the majority of runners heel strike.

Root discussed the formation of forefoot calluses secondary to shearing forces associated with propulsion as well as to the central metatarsals due to increased loading for an excessive period of time and abnormal shear. Root’s observations hold true for someone who heel strikes when running as we see increased force placed upon the forefoot during what he described as the propulsion phase. Observation of the gait of a barefoot runner or one who strikes with the forefoot/midfoot demonstrates that the propulsion phase as described by Root becomes very minimal in existence, if it even occurs at all.

Good Form Running in association with New Balance provides training to adopt this style of running and we can see that by developing forward momentum, we carry the contralateral limb forward. By doing this, we decrease the force present to the forefoot, especially the shear force. Not only is this beneficial for reduction of the shear force but we see a decrease in the ground reactive forces acting on the first metatarsophalangeal joint, which can reduce sesamoiditis.

Vibram started making the five-toed shoes in 2006 and since then the FiveFingers brand have become so popular that the company has had problems keeping them in stock--and stopping counterfeiters from selling knock-offs online.



If you’re thinking about shedding your shoes, consider these guidelines:

  1. Barefoot training is not for people who are just starting to run or returning from a long layoff--it’s something to slowly incorporate into an existing running regimen.
  2. If you have persistent or serious foot problems, consult your podiatrist first.
  3. Ease in slowly. Paul advises starting with a few minutes on a flat, relatively forgiving surface once a week. Grassy fields, smooth roads, and soft trails qualify. Running on sand might be tempting, but barefooting newbies should stick to wet sand at first as the unstable soft stuff puts a lot of torque on your joints and is much harder to run on.
  4. Listen to your body. “Barefoot Ken Bob” Saxton, founder of runningbarefoot.org and finisher of more than 70 barefoot marathons, says, “Luckily, your feet are sensitive, which is a good thing. Listen to them and they'll keep you from doing something stupid.”


Tammy McKenzie
is a certified personal trainer and fitness specialist with a speciality in women's fitness.


Sources:
yahoo.com
google.com/hostednews
sock-doc.com
mytreadmilltrainer.com
sciencedaily.com
livescience.com


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