Chances are, you’ve heard about minimalist running shoes and their purported benefits, and may be curious about all the hype surrounding them. While there are select circumstances where minimalist shoes may be suitable, they are not an appropriate choice for most runners.
Here is what you need to know:
What is minimalist running?
Minimalist running means that: 1) you use no shoes when running or 2) you use a shoe that has been specifically designed to have certain attributes to it that will prevent the shoe from altering your gait.
Minimalist shoes have become so popular that there is a huge spectrum of just how minimalist a shoe can be. A recent paper was published in the Journal of Foot and Ankle Research that can be read here that seeks to standardize just how minimalist (or maximalist) a shoe is on a scale of 1-100.
For example, on this scale a Vibram 5 Finger shoe would receive a very low score and a Hoka One One shoe would receive a very high score.
These scores are based on five different attributes of the shoe:
- shoe weight
- stack height (the thickness of the sole of the shoe at the heel)
- heel to toe drop (the difference between thickness of the shoe's sole at the heel and at the forefoot) 4) motion control or stability technologies
- shoe flexibility (when twisting and bending the shoe from end to end)
A VERY minimalist shoe will be a shoe that:
- is extremely light
- has a low stack height
- has a minimal heel to toe drop
- has no stability features
- is very easily twistable AND bendable.
Extreme supporters of the minimalist movement often contend that the current shoe industry has fabricated big, bulky, overpriced shoes with all kinds of features that are leading to an increase in the incidence of running-related injuries. They claim that today's running shoes cause runners to favor a heel strike rather than forefoot strike; they claim that heel striking is not natural and that it leads to an increase in impact and impact-related injuries. I disagree with this contention.
Contrary to the minimalist argument, most runners are not natural forefoot strikers. I have been running since about 1990. I started running track as a high school freshman and have been competing regularly since then. I ran varsity high school track and cross country, as well as 12 seasons of collegiate track and cross country . After college I competed as part of several different running clubs. During this extensive exposure to the running community prior to the minimalist movement, I have seen very few true forefoot strikers. In fact, less than 5 percent of runners are true forefoot strikers. The abstract of two really good studies that demonstrate this can be read here and here.
Also contrary to the minimalist argument, forefoot striking is not the “superior” running form. Proponents of minimalist running often contend that forefoot striking is more economical and prevents impact injuries. Both of these claims are false. To say that forefoot striking is a better way for everyone to run is simply not true.
Forefoot striking means that the first part of the foot to strike the ground is the ball of the foot. When this happens, the calf muscle must contract to slow the heel down and prevent it from smashing into the ground. In research papers, this has become known as the metabolic cost of cushioning.
When the calf muscle contracts in this manner, it uses more energy than heel striking. As a result, forefoot striking is less economical than heel striking. This was shown in studies here and here. If you look at pictures of the fastest runners in any marathon, you will see most of them strike with the heel first at the point of foot impact. The fastest long distance runners in the world are mostly heel strikers, including Meb Keflezghi, Deena Kastor, and Dennis Kimetto.
Forefoot striking can reduce certain impact-related injuries. However, because the forefoot strikes the ground first, this style of running can elevate the chances of sustaining a forefoot injury. Additionally, because the calf muscle must repeatedly fire to slow the heel from impacting the ground, forefoot striking can also cause Achilles injuries.
In my professional opinion, when using minimalist footwear, a runner is much more susceptible to certain injuries including metatarsal stress fractures, morton's neuroma, capsule and tendon injuries to the forefoot, blisters, puncture wounds, Achilles tendinitis, and Gastro-Soleal (calf muscle) strains and pulls. I have personally seen multiple examples of such injuries in my office.
Most modern running shoes are built with an EVA (ethyl vinyl acetate) or PU (polyurethane) midsole. The running shoe industry has been using these materials since the 1970s to create the soft spongy layer that sits between your foot and the outsole of your shoe. Similar to wrestling mats, these materials absorb shock. If you fall on pavement, it hurts. If you fall on a wrestling mat, it doesn't. As a principle of simple physics, it is clear that EVA and PU midsoles reduce impact. To say that modern conventional running shoes cause more impact than minimalist type running shoes is obviously false.
Impact reduction is essential for the modern day runner. The surfaces that most recreational runners choose to run on are now artificial. Pavement and concrete pathways create a very consistent surface on which a runner can crank out many miles in little time. However, these man-made solid stone pathways do not absorb any of the impact imparted on them by the foot. All of the impact is absorbed by the human body. Additionally, the consistent nature of the surface multiplies repetitive stresses on the musculoskeletal system. For these reasons, minimalist running on a pavement or concrete surface is very dangerous. The modern running shoe, on the other hand, attempts to reduce some of the impact forces by placing an impact reducing material between your foot and the ground.
Is it the shoe for you?
While minimalist running is certainly not appropriate for everyone, it may be suitable in some circumstances. If you choose to try minimalist running, there are some things you can do to reduce your injury risk. There will be an adaptation period where you may experience soreness in multiple areas after initiating this type of running. During the adaptation period, it is important that you do some of your runs in minimalist footwear and some of your runs in conventional footwear. The best surface on which to try minimalist running will be grass athletic fields. The grass surface will absorb some of the impact that would otherwise have been absorbed by your shoe. Other surfaces that are more desirable than pavement are synthetic track, treadmill, and crushed stone.
People that have a high body mass index (BMI) should be very cautious as the extra body weight applies more impact forces with every step they take. Also, anyone with an abnormal gait pattern or abnormal orthopedic structure needs to take that into consideration as that can increase risk of injury. In general, the people that will have the least risk with minimalist running are people with a low BMI/ body weight, a neutral efficient stride, and slow pace. If you are a heavy person running on pavement at a faster pace, your injury risk will be much higher.
While the minimalist footwear and forefoot striking may be beneficial for a select few (for example people with anterior compartment syndrome as shown here), the risks usually outweigh the potential benefits. In the vast majority of the population, conventional running shoes and heel striking are more practical.
Modern running surfaces have become very hard and unforgiving. Many of us have a high BMI. Most runners want to run faster rather than slower. So unless you can lose weight and jog endless, slow circles around soccer fields, I suggest you go out and buy a nice supportive and cushioned pair of running shoes and head to the nearest jogging path.
Dr. Crispell is a foot and ankle specialist at Riddle Hospital in Media, PA. He is a guest contributor to Sports Doc.
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