My first introduction to the idea of barefoot running was watching the African barefoot Olympic athletes in the early 70s. I couldn’t help but think, “How can it be comfortable to run a full marathon barefoot?” Based on my own experience of growing up wearing shoes most of the time, I couldn’t understand how someone could run for 26 miles unshod when I could barely walk across the driveway. Based on my studies of biomechanics, the body and genetics, I now understand how this is possible.
For the past 34 years, my life has been committed to working with feet and shoes in all areas of sports application. My understanding of foot biomechanics is based on years working with Chris Smith, DPM, co-founder of Northwest Podiatric Laboratory, one of the most revered custom podiatric labs in North America, and also through my studies and work as a Certified Pedorthist and Director of Education for Superfeet Worldwide.
I think it’s important to get back to basics and look at our anatomy and our history when considering whether it’s best to wear shoes or go barefoot. Maybe the better question is: when is it best to wear shoes, and when is it best to go barefoot?
WHAT IS THE FOOT FOR?
Before we even get into the training, muscle building, and terrain aspects of ambulation, it helps to understand the primary function of the foot. The foot primarily acts as a rigid lever so it can hold the body in a vertical position while propelling across the terrain.
The secondary function of the foot is to perform as a mobile adapter that adjusts to uneven surfaces and has the ability to absorb shock when it comes in contact with the supporting surface.
Some of the earliest feet documented in archaeological records were very rigid, high arched, stable feet. These feet were ideal for walking on uneven terrain and for climbing: for the terrain that humans were adapting to in their natural surroundings. Several million years ago (even a few hundred years ago!), the earth was not flat with asphalt, concrete, cement, or wood and marble floors – it varied in its topography, and therefore the foot was shaped three-dimensionally.
To sum up: the three-dimensional foot was designed for the three-dimensional earth.
WHAT ARE SHOES FOR?
So what happened when humans got tired of burnt, scratched and injured feet? Shoes.
The very first covering for the foot was found to be used up to 40,000 years ago, and was first utilized to protect the foot against the outside elements, including changes in weather and foreign objects that could damage the bottom of the foot.
Shoes have seen their own evolution through the years as humans have become more technologically adept, shifting from simple hide or grass coverings to their current existence as the epitome of style and fashion, and less frequently, comfort.
WHAT ABOUT FOOT TYPE?
Let's look at genetics. What it all comes down to is whether or not someone has a stable foot – this can make all the difference in barefoot running or walking. There are individuals who have the genetics to run barefoot completely healthily.
Historically, most of the Olympic athletes who have run marathons barefoot and placed in the top 10 had stable feet. There's a lot to say about a good stable foot!
But it is rare that you will see an unstable, pronated foot running a marathon barefoot.
Many successful East African barefoot runners like Abebe Bikila most likely grew up barefoot and worked in the fields or on ranches barefoot. Some may have lived every day walking and running barefoot outside, possibly running the equivalent mileage of a marathon herding sheep on a daily basis. Spending one’s entire life barefoot on uneven surfaces obviously sparks an adaption process that starts to take place at a very young age.
For people who are barefoot runners from birth, much also depends on their own personal genetics – some people are just better genetically engineered to run barefoot while the majority of us are not.
In addition, every person has their own particular running style based on their biomechanics, and each person's body will automatically settle into their best running efficiency. The body will always find the most efficient position for which it is built. This will also have an effect on the success of barefoot running. For example, a normally shod runner whose body's best efficiency is during heel strike may feel pain in the heel when running barefoot. If the heel hurts, the runner will automatically change his/her running efficiency to land midfoot, which may help to alleviate some of the pain at heel contact. However, the runner may no longer be running at his/her body's ideal efficiency based on their biomechanics.
WHAT DOES RUNNING OR WALKING BAREFOOT ACCOMPLISH?
I do believe that running barefoot can be a strength and muscle-building tool that you can use for training.
Periodically it's good for bare feet to walk or run on grass or soft terrain that is safe from sprinkler heads, rocks, broken glass or sharp objects. This type of environment gives the foot and lower extremities the chance to use the muscles in a slightly different way, which helps with coordination, balance and conditioning. However, it's human nature to take it too far, too long and too hard.
This is when we experience muscle strains, sprained ankles, ruptured and torn muscles, tendons and ligaments. Know your own body: know when to back off, know when to quit, and know when to keep going.
The human foot has a built-in shock absorbing fat pad on the plantar sole. The thick fat pad underneath the heel bone absorbs shock at heel contact, whereas the fat pad under the ball of the foot is much thinner. The forefoot was not designed for impact and shock absorption, it was intended for propulsion.
The natural shock-absorbing fat pad on the bottom of the foot does eventually deteriorate over time – this is most evident in seniors who have spent the majority of their lives working on their feet. It's too early to tell, but I think one of the long-term effects of barefoot running could be the earlier deterioration of the foot’s natural fat pad. As I mentioned earlier, the fat pad was designed for softer, uneven terrain, not constant contact with today’s flat, hard surfaces.
Also, because many – if not most – people in the U.S. have grown up wearing shoes and walking or running on paved surfaces, most have adjusted or adapted their natural stride to shoe-wearing. Therefore, if they wear an appropriate shoe that is properly sized and fit for the application, it will allow them to walk or run much more efficiently. This is easy to observe: simply have an individual walk barefoot – then have them put on a shoe. You will notice that they walk much more efficiently with the shoe.
There are a number of soft shoes/gloves currently on the market created for ‘barefoot’ running, but if you put a covering around the foot with a rubber sole on the bottom and a pocket for each toe, then the foot is no longer bare. Basically, running in gloves (non-supported footwear) just means there is a layer there to protect you from cuts, punctures and extreme temperatures. Some of the softer shoes on the market are made with a wide outsole on the heel which when used on a hard, flat surface actually increase the pronation forces and work as pronation accelerators. If using or testing these products, make sure to follow the manufacturer's recommendations for training purposes.
It comes down to the fact that a shoe does not take away the ability for the foot and body to build strong muscles in the feet. The muscles in a flat foot work at their maximum strength capacity just like the muscles in a stable foot – the flatter foot’s muscles just need to work a little harder in order to help that foot function.
PUT IT IN YOUR TOOLBOX
Basically, for people who have grown up wearing shoes, I think it's a good idea to periodically go barefoot on the beach or in the yard to give those foot muscles a different type of workout…just like it's a good idea to change shoe style from time to time for the same reason. But I am concerned about the number of people who may try running barefoot without realizing that they may not have the genetics or stable foot to maintain it in a healthy manner. Remember: use pain as a signal to know when enough is enough. Running barefoot is just another tool in your toolbox – know when to use it.
Jeff Gray, C.Ped.
Director of Education