Foot News

Injuries Observed a Minimalist Runners: Does this mean I should go back to my old running shoes?
September 24, 2013

This article discusses:

  • Recent case reports illustrating the relationship between minimalist shoes and running injuries.
  • A sensible approach to thinking about shoe wear especially minimalist shoes and foot stress.
  • Minimalist shoes can be a healthy part of running if they are used correctly.

left banner imageFitness now is as popular as it ever has been. Since the publication of Chris McDougall’s book, Born to Run, the minimalist running movement has gone from a small fringe of the jogging community to a significant market that has attracted the attention of all sports shoe manufacturers. The supposed benefits of the minimalist running style are many. Studies have shown a reduction in the initial impact when running without shoes. The changes in the way in which the foot hits the ground and stride cadence have lead its proponents to infer that minimalist runners may see increases in performance and decreases in running injury.

Although I believe that the scientific evidence behind the advantages of barefoot or minimalist running style is still limited, I wholeheartedly believe that it is a healthy method of exercise. The use of shoe wear, especially athletic shoe wear, is a recent development in human history. Our feet have evolved to run and to develop and function without shoe wear. Medical science is finding that often, when we take our bodies away from their natural state, the state that they have evolved and thrived in, negative consequences occur. There are many examples of this. While there is no doubt that sanitation has been a benefit to humans, our sterile environment and the absence of parasites within our body has been suspected of causing many of the asthmatic (reference) and autoimmune diseases (reference) (such as lupus, rheumatoid arthritis and bowel diseases) that we are experiencing in modern society. While no one relishes the thought of little worms and parasites feeding on our bodies, they have been a universal fact of our existence thoughout human history. The default settings on our immune systems take them into account. Our more refined and processed food diet has led to an increase in diabetes, obesity, and heart disease. Our more sedentary lifestyle has also caused many health problems, which I probably do not need to clarify.

Feet are likely to be no exception. “Protection” or “support” in shoewear is not a natural state. Feet that develop in shoes have been shown to have a higher incidence of hallux valgus/bunions (several references, one most recent) and pes planus/flat feet (most recent reference). There is no evidence that the modern running shoe has decreased the incidence of running injuries and some to indicate that it has increased them. The lack of stimulation in the shoed environment may make the foot hypersensitive. The skin becomes thinner and its important cushioning function may not be as robust, leading to impact pain, prominent bones, and plantar corns. Because the irregularities of the ground are dampened by shoes, the foot bends and twists less (reference). The bending and twisting adaptation is controlled by the small and large muscles in the foot. They may become weaker as a result. The weakness in these muscles may expose the ligaments, and joints to more tension, damaging them. Potentially, this may lead to plantar fasciitis/heel pain, fallen arches, hammertoes, bunions, and midfoot arthritis.

Dr Salzler and his colleagues (Salzler et al., Foot and Ankle International, 2012:33, page 262 – 266) have noted that, since the minimalist running movement has become more popular, he has begun to see stress injuries as a result. He does not claim that the injuries are more frequent than in runners wearing standard shoes; he merely is identifying these problems and giving doctors an idea of common injuries associated with initiating a minimalist running style. The injuries included stress fractures of the heel and metatarsals, and a plantar fascial rupture. Most began soon after the initiation of the minimalist running. Some of the runners abruptly switched their running shoes without a transition period. This problem should not come as a surprise and here’s why:

Our tissues react to thier mechanical environment according to a law that a German surgeon, Julius Wolff, described in the 19th century. It states that the tissue (his work focused on bone, but all biological tissue seems to adapt the same way) adapts to the stress that is applied to it. Simply stated: If our tissue sees a lot of stress, eventually it will remake and modify itself to adapt to this stress, to become resilient enough to withstand it. This works out pretty well unless we overload the structure. If the tissue stress and subsequently the damage to which we subject our body, overwhelms our body’s ability to repair itself, then it accumulates until it finally breaks. This means that, when we intensify our activities either by doing more or doing our activity in a way that stresses certain areas more, it needs to be gradual to avoid injury. If we decide to adopt a barefoot running style, we must incorporate it into our workout gradually. It takes time for the bones, muscles and ligaments to adapt to our different stresses. How gradually? No one knows for sure and it is probably different for each individual.

I believe that a good rule of thumb (that doctors seem to commonly quote, but is not scientifically proven) is 10% per week. During this adaptation period, it is important to stay consistent in our workout, meaning the same intensity every day as long as the increase is painfree. If you run 10 miles per week, begin by running for 1 mile in minimalist shoes and 9 miles in your standard running shoe. It may be frustrating because you’re enthusiastic about your new shoes, but it will pay off in avoiding stress injuries. If you begin to feel swelling or pain, especially a pain that is consistently in one location on your foot, you will have to decrease your activity until this pain goes away. When it goes away, you will have to resume and increase your regimen more slowly. Everyone is a little different about these things and the older you are and the more medical conditions that you have, the more prone to stress injuries you will be. If the pain or swelling does not go away or intensifies in spite of the decrease in activity, get it checked out by a doctor.

Like many things in medicine, the scientific evidence to support barefoot and minimalist running is not strong or conclusive yet. From a conceptual and philosophical standpoint, there is some merit in this idea. Minimalist running and barefoot athletics promises to increase the resilience of our feet and may have many other benefits to the joints and bones of the leg. However, if it is incorporated into your routine, it should be adopted in a progressive, reasonable and safe fashion. It should be possible to reduce the possibility of stress injuries by gradually incorporating it into our activities.

–Brett Fink, MD. Co-author of The Whole Foot Book: A Comprehensive Guide to Taking Care of your Feet