Doc, what do you think of these new ‘brand x’ orthotics they sell at ‘random store?”
“Doc I just bought these new super padded walking shoes I saw on TV. What do you think of them?”
Before I answer any more questions about individual orthotics and highly engineered walking and running shoes, let me explain my thoughts on the human foot first.
First, I will share a couple personal anecdotes.
In my younger, rugby playing days, I was prescribed a pair of custom orthotics to train in from a podiatrist who was very well known in my hometown. I didn’t know much about training or anything about anatomy at the time, so I was excited to start wearing them. I inserted them into my shoes and carried on with regular training.
While doing speed training in the offseason, I felt a sudden pinch in the sole of my right foot. I ignored it (as 20 year olds often do) and carried on training for the day. When I got home and got my shoes off was when I felt the searing nature of the pain. Turns out I had torn my plantar fascia. I managed to get in to see another podiatrist who had informed me that there was some preliminary evidence showing that certain orthotics have been linked to actually CAUSING tears in plantar fascia and predisposing people to plantar fasciitis.
Fast forward to my early 30’s. I had enlisted in the Army National Guard and was preparing to go to basic training. Up to that point I had been running in a minimal shoe. I took the necessary steps to effectively run in a minimal shoe without injuring myself. In the 5-6 years preceding my enlistment I had run several longer races in minimal shoes, made my running gait more efficient, and had spent time training my feet to grow stronger and improve balance and proprioception in my feet and ankles. I was pretty well versed in running in a minimal shoe. (*side note:* this past November, I ran 33 miles in a single day in a minimal shoe and had zero issues with foot or lower leg pain. I couldn’t say the same about my stomach however). Making the switch to a minimal shoe had eliminated the ankle, and shin problems I had become accustomed to.
When I shipped to basic training I was informed that I had “flat feet” and was forced to wear a very highly engineered, super padded, highly motion controlled shoe because of my “flat feet.” By the second month of basic training, I had developed plantar fasciitis so bad I could hardly walk in the morning. Each morning I awoke with searing pain in my heel that would only remit after we started doing our warm up for the day’s physical training at 5 AM. To be fair, I’m not putting all the blame on the running shoes; the standard issue boots the army gives are pretty terrible as well. The key point to the running shoes is that they were so padded and motion controlled that it once again altered my running gait back to a heel strike rather than the POSE method mid foot strike I had for so long. It took some very good acting for me to hide the injury in basic training, and was only asked about why I was limping the day before we graduated. The pain continued for about 6 weeks after basic training (yes, sometimes it takes that long to rehabilitate).
So, what do I think about orthotics and big clunky walking and running shoes? Here is what I think about feet.
The foot is a marvel of design. Millions of years of natural selection lead to the development of a structure consisting of 26 bones supported by a vast system of muscles and ligaments. These structures evolved to support humans standing, running, and walking in an upright posture (as opposed to our four legged friends). Much of this standing, walking, and running was performed in little to no footwear, often times footwear consisted of just enough protection to protect the soles of our feet from sharp rocks and environmental hazards. Highly padded shoes that are advertised as being supportive and for certain feet types are a modern invention.
The structure of the foot depends on the strength and integrity of many of the muscles in the foot. Yes, there are muscles in your lower leg and feet, lots of them. The muscles of the lower leg act to support the arch. Just like any other muscle in your body, if you don’t use them you will lose them.
Imagine that you broke your arm. Chances are you would be put into an arm cast for 4-6 weeks, maybe even longer. When the cast is removed, what happens to the muscles of the arm? Are they as strong as the muscles of the other arm? Are they as strong as they were prior to being put into a cast? Of course they wouldn’t, you haven’t used those muscles for the length of time they have been in the cast. A certain degree of atrophy will have set in during that time. Depending on the length of time you were in a cast, your ortho may even prescribe physical therapy to rebuild the strength and function of the arm.
In a study titled “The effects of short foot exercises and arch support insoles on improvement in the medial longitudinal arch and dynamic balance of flexible flatfoot patients,” the authors noted:
“Although the feet occupy only 5% of the areas of the human body, they control postures through afferent information obtained through the sense of the soles, provide stability for maintenance of balance, and absorb impacts1).
The deformation into flatfoot is induced when the medial longitudinal arch (MLA) has descended because the arch had been excessively relaxed to the extent that the arch cannot be maintained and causes the feet to be excessively pronated compared to normal feet so that heel eversion appears and the weight load is shifted inward to compress the MLA2, 3). When the MLA has descended or has been completely lost leading to structural or functional deformation, the ability to absorb impacts will decrease and the sense of balance will be lost so that stability decreases during walking or running leading to walking difficulties and endurance decreases4, 5).”
The sections I put in bold are important. Your foot is a dynamic structure. It adapts to different stressed being placed on it. Ever go for a barefoot walk on the beach? How your your lower legs and feet feel after the walk? Chances are, they are very sore and fatigued from having to work so hard to maintain your posture and balance on the soft sandy surface. That is a straight forward example of your body and muscles at work to adapt to the environment.
Ever try to balance barefoot on one leg? Better yet, ever try to balance barefoot on one leg with your eyes closed? Go ahead, try it (make sure nobody is watching). Was it difficult? That type of balance is dependent upon the strength and proprioception of the muscles of the hip, leg, lower leg, and foot. Did you feel your foot collapse inwards while trying to balance?
Your foot behaves in the same manner as any other joint structure in your body. Want to improve your leg, hip, and core strength? You’ll probably need to develop some squatting and deadlifting ability. Just like any other system in the body, the feet, ankles, and lower legs can become de-conditioned, weak, and prone to fatigue leading to potential injuries.
So what do I think about the fancy new shoes and insoles on the market? I think in the case of acute injury they can be very necessary. When your foot is in pain, I am all for some type of custom orthotic to get you through the acute phase of pain. However, you had better be rehabilitating your foot. Just like the arm cast example I gave above, long term dependence on orthotic insoles and large highly engineered running and walking shoes can lead to de-conditioning of the muscle groups I had mentioned above, which could prevent a chronic condition from improving, or worse yet, make it worse.
In an article titled: “Avoid Running into Trouble: Orthotics Can Cause Problems if Improperly Prescribed,” Rick Positano DPM states that "Orthotics are like prescription drugs," Dr. Positano explains. "When indicated and prescribed correctly, they are beneficial to the user. When unnecessary or prescribed incorrectly, they can be dangerous." Some over-the-counter orthotics may exacerbate pre-existing medical conditions, Dr. Positano says. Those at particular risk are people with heel pain, achilles tendon pain, back or knee problems, or those who have a high arch foot type or flat feet. Exercise enthusiasts who engage in high impact or high velocity sports often buy orthotics to provide support or serve as shock absorbers. That, too, can spell trouble.”
The article goes on to say: “Orthotics are not used to correct foot and ankle problems. Health care professionals prescribe them to stabilize a joint, reduce pain, prevent deformity, provide better positioning or improve the biomechanical function of the foot, according to Dr. Positano.”
Improper footwear and long term use of orthotics have the potential to cause your feet to lose their adaptive capabilities and strength. By controlling motion and controlling the mechanics of your feet, they are negating your own muscle's ability to support the structure of the feet therefore potentially causing the muscles to atrophy (just as postural muscles in your core lose the ability to support your trunk if you sit at a desk all day.
Over time, this loss of functional ability leads to a foot that can't do what a foot is supposed to do. Support your body, balance, and provide feedback to the rest of the body in regards to posture.
To summarize, if you have an acute condition, by all means hit up your podiatrist and have them examine you, but make sure you are taking active steps to rehabilitate the muscles of the lower leg and foot. Your foot is a dynamic structure that behaves like any other part of the body. Rehabilitating and strengthening the structural integrity of the foot and lower leg can be very time consuming, but it is an incredibly important step towards developing a pain free and strong foot.
1) Kim, Eun-Kyung, and Jin Seop Kim. "The effects of short foot exercises and arch support insoles on improvement in the medial longitudinal arch and dynamic balance of flexible flatfoot patients." Journal of physical therapy science 28.11 (2016): 3136-3139.