Note: This is part 1 of a series covering the topic of minimalist footwear & running form/style to prevent injuries and promoting life-long healthy living habits. (Find Part 2 here) We’ve also created an 8-week training program and book on the subject that you can find here or on amazon. You should always consult your doctor or another licensed healthcare professional, like a physical therapist, before making any drastic changes to your footwear or running style as it may lead to an injury.
It’s that time of year again. Winter seems to have begun to release its grip on the world. The days grow longer and the weather warms up a bit. And many people begin to dust off their running shoes and make plans to return to outdoor running programs. Even if you’ve been running through the winter, one thing is certain: springtime tends to be a much more pleasant time to run, especially outdoors, than the depths of winter.
With that being said, many runners experience a series of pains, aches, and injuries over their running career. Plantar fasciitis, heel spurs, shin splints, and knee pain are among a few of the most common running-related injuries. In an effort to overcome, bypass, or recover from these types of injuries, many runners turn to “minimalist” or “barefoot” shoes for running. This typically includes either using shoes with zero toe drop (more on that in a bit), minimal support, and even just running on bare feet.
Now, this idea of “barefoot running” meets both harsh criticism or great praise depending on who you talk to. Some doctors, physical therapists, trainers, and runners think that running with minimal cushion or heel lift leads to increased injuries and pain. And some doctors, therapists, trainers, and runners say that barefoot running is the most natural way to run and that it leads to fewer injuries over the long run.
So which side of the argument is right?
Well, to answer that question, we must first break down the components that make up “barefoot running”. Mainly, we need to talk a bit about the shoes themselves and then, we need to look at the running technique associated with barefoot running. To do that, we’ll break this topic up into two different articles. This first one covers minimalist and barefoot shoes and footwear. The next article will cover the technique of barefoot, or forefoot, running.
We’ll start by defining what we actually mean when we say “barefoot” or “minimalist” shoes. Then we’ll review what the research says about this type of footwear.
Defining “Barefoot” and “Minimalist” Shoes
When you hear the term “barefoot shoes”, you may think of shoes that look like your feet. “Toe finger shoes”, like those sold by Vibram, certainly fall into this category, but there are more options out there. To begin, let’s look at what’s considered “minimal” in the footwear department.
Typically, barefoot or minimal shoes have the following features:
- Minimal (or no) cushion or stability supports, especially in the heel
- High flexibility of the sole
- Zero heel-to-toe drop
- Wide toe box
In order to try and standardize the definition of “minimalist footwear”, the folks over at the Journal of Foot and Ankle Research came up with this: “Footwear providing minimal interference with the natural movement of the foot due to its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices” [9]. To put it simply: minimalist or barefoot shoes provide little to no cushion, arch support, or heel lift.
And shoes fall all along this spectrum from maximal shoes to minimalist shoes. For example, some shoes like the Altra Viho, provide no heel lift. So they’re zero drop. They have a wide toe box. But, they are less flexible and provide a bit of cushion. Then you’ve got something the Merrell Vapor Glove, which provides no cushion, is highly flexible, has zero heel-to-toe drop and a wide toe box. (Now, those two examples represent some of the big names with high price tags. There are more affordable options like the Whitin Shoes)
Now, why would someone consider wearing, as my wife calls them, “socks with rubber soles”? Essentially, these minimalist shoes provide no (or very minimal) cushion. They’re basically a firm, thin rubber sole attached to the top of the shoe.
The reason behind this stems from big words like proprioception. Now, that’s a big word that means “your body’s awareness of itself in space”. Proprioception keeps you from walking in a zig-zag pattern down the road. It prevents you from falling over on your side when you’re sitting down at your desk. And, more importantly for this topic, proprioception helps your body’s muscles know how much to contract, when to contract, and when to relax during walking or running. All those small muscles in your foot & ankle, as well as the large muscles in your leg and thigh, rely on your body’s proprioception to time movements, control those movements, and to keep you stable on the move.
So, minimalist or barefoot shoes are designed to give your body more proprioception. By removing thick cushions and soles from the bottom of your feet, the nerves at the bottom of your feet get a more clear or realistic picture of the ground you’re walking on —so the theory goes. They’re also designed to encourage appropriate body mechanics during running. For example, big heel cushions and foam supports limit your body’s proprioception or “ground feel” while running. This can lead to taking wider, longer steps, and landing on the heel of your foot. When you land with your outstretched leg on your heel, the force travels directly up your leg to your knees, hips, and back. And the force of that impact may lead to increased injury rates.
Now, to better understand this topic, let’s take a brief look at the literature & research around barefoot & minimalist shoes and their impact on biomechanics and joint stress.
Research Around Heel to Toe Drop & Barefoot Shoes
Now, it’s been almost a decade since the whole “barefoot running” trend took ff here in the United States. So, in that time, we’ve had plenty of opportunities to research & study the differences between shoes that provide a lot of support and shoes that provide nearly no support. What I’ll do here is point out a few findings from the research and then discuss what that actually means for everyday life.
Stability
Now, this should come as no surprise, but research does show that running with barefoot or minimalist shoes results in lower stability while running [1]. Obviously, a shoe that provides no cushion or support does not provide stability. And running barefoot has been shown to acutely affect running stability. What is interesting, is that this decreased stability is more pronounced in runners who have been “habitually shod runners” [1]. That basically means, people who normally run in stabling shoes experience greater instability when they begin to run in barefoot or minimalist shoes.
The theory here is that, because these cushioned shoes decrease sensory input (lower proprioception and tactile input), runners that normally run in cushioned, non-flexible shoes develop running patterns that are less stable. But, since, they’re wearing stabilizing shoes, they don’t experience a lot of instability with running [1]. Now, as I’ll discuss below, those altered running (or gait) patterns may actually increase the forces on other joints and lead to other injuries over time. But, it’s worth noting that, if you switch from traditional shoes to barefoot or minimalist shoes, you will likely need to do it over time to account for the changes in running pattern that will need to happen. Even if it’s a small change, when you multiply it by thousands of steps over the course of a long run, it has great impacts on your joints [3].
Comfort
One interesting study involved hiking boots and heel rise (or heel-to-toe drop). The study found that comfort measures decreased —meaning the participants in the study were less comfortable— as time went on, particularly in shoes with high heel drops [5]. This may be due to the way heel drop can affect the biomechanics of walking. For example, keeping your heel lifted means that your calf muscle is always shorter than when you are barefoot, which may impact the way you take steps and land on your feet. This may impact comfort over time.
Joint Forces
Now, this topic has a lot of mixed information in the research. Many studies show that running in barefoot or minimalist shoes results in reduced joint reaction and muscle force, lower impact on the joints, and increased improved energy efficiency [2][3][6]. However, there are also studies out there that seem to show that maximalist shoes do not alter performance or joint mechanical output [4]. There is some evidence that suggests stiff cushioned shoes may lead to leg stiffness during the landing phase —usually landing on your heel— that increases to force and impact through your knee and hips [3]. This research also seems to show that, for faster or longer-distance running, the greater injury risk that is associated with stiff shoes may not be related to the direct joint forces so much as biomechanics or movement patterns putting more pressure on certain muscles or joints [3].
One thing seems to be emerging from the literature: shoes may not matter as much as gait pattern and foot strike. For example, the article about running stability said that there was decreased stability with running in minimalist shoes when the runners normally wore traditional shoes [1]. This probably has less to do with the shoes themselves, and more to do with how the runners run. What running and movement habits have we developed because of the shoes that we wear? And can these habits be changed so that, with time, transitioning to barefoot or minimalist shoes doesn’t lead to decreased stability or increased joint forces? The research is lacking here. In fact, that article mentioned that there’s no current evidence-based methods for transitioning to minimalist shoes, but research should also be done on runners that have been running barefoot or in minimalist shoes to get a better idea about stability, joint force, and injury rates [1].
Running Biomechanics & Injuries
Here’s where the rubber meets the road, both figuratively and literally. All the talk about shoe types and cushion or heel-drop seems to miss the mark. The focus should be on the biomechanics or the movement patters that runners use when going out for their morning (or evening) runs, as well as how our shoes affect those movement patterns. The research seems to show that, having cushioned or minimalist shoes alone isn’t enough to prevent injuries. The biomechanics —or how we run in those shoes— causes or prevents injuries. Still, research shows how certain types of shoes affect the biomechanics or movement of runners.
Barefoot/minimalist running has been associated with lowered joint loading and impact on certain parts of the body like hips, knees, and ankles [2]. This, however isn’t because the shoes themselves protect the joints any better. These shoes, with their minimal cushion and support, encourage runners to adopt a different stride pattern, and it’s that different stride (or gait cycle) that reduces the impact or forces on the joints.
That’s why some studies shoe that even cushioned shoes with minimal to no heel-to-toe drop decrease patellofemoral (knee) joint stress [8]. For example, shoes with large heel drops significantly increase peak knee extension momentum, which amplifies the impact of landing on that leg [7]. It seems that heel-to-toe drop significantly influences the running patterns and affects joint loading during running. So, simply making small adjustments to the shoes, instead of going all the way to barefoot, impacts the gait cycle enough to have positive effects on joints.
Summary
The topic of which running shoe is best can be a rather controversial one to approach. There are good arguments on both sides of the aisle, with research to support the arguments being made on each side. That’s why we always encourage people who are considering shoe changes to discuss those ideas with a qualified licensed clinician.
Either way, one thing seems to be evident in the available research: shoes alone won’t save you! While it sounds nice to think that simply buying a maximalist shoe, or going all the way to a barefoot shoe, will prevent or reverse running injuries, that’s not always the case. In fact, the transition from very supportive and stiff shoes to barefoot shoes causes an increased injury rate in runners, mainly because they don’t take the time to make the transition correctly.
Think about it: if you’re used to running with thick soles and a lot of arch support and then one day you simply remove all of that cushion and support, do you think you’ll be able to go out and run your regular distance? Of course not. It takes weeks or even months to successfully and safely transition from traditional shoes to barefoot or minimalist shoes. That’s why many runners who try and make the change get injuries: they try too much too quickly. The transition to barefoot or minimalist running requires almost a relearning of how to run, using the right muscle, stride pattern, and running technique. And that is the topic of the next article.
If you are a runner that’s trying to come back from an injury, or you’re considering some major change in your running technique or footwear, consider our Complete Runner’s Assessment. This assessment includes everything needed to start the pat towards pain-free running.
References:
[1] Hollander, K., Hamacher, D. & Zech, A. Running barefoot leads to lower running stability compared to shod running – results from a randomized controlled study. Sci Rep 11, 4376 (2021). https://doi.org/10.1038/s41598-021-83056-9
[2] (2021) Reduced joint reaction and muscle forces with barefoot running, Computer Methods in Biomechanics and Biomedical Engineering, 24:11, 1263-1273, DOI: 10.1080/10255842.2021.1880572
(2022) Lower impact forces but greater burden for the musculoskeletal system in running shoes with greater cushioning stiffness, European Journal of Sport Science, DOI: 10.1080/17461391.2021.2023655
[4] (2021) Maximalist shoes do not alter performance or joint mechanical output during the countermovement jump, Journal of Sports Sciences, 39:1, 108-114, DOI: 10.1080/02640414.2020.1808277
[5] (2021) Plantar pressure distribution and perceived comfort in hiking boots with different heel-to-toe drops before and after 45 minutes of walking,Footwear Science, DOI: 10.1080/19424280.2021.1991007
[6] Yu P, He Y, Gu Y, et al. Acute Effects of Heel-to-Toe Drop and Speed on Running Biomechanics and Strike Pattern in Male Recreational Runners: Application of Statistical Nonparametric Mapping in Lower Limb Biomechanics. Frontiers in Bioengineering and Biotechnology. 2021 ;9:821530. DOI: 10.3389/fbioe.2021.821530. PMID: 35155415; PMCID: PMC8833076.
[7] Zhang M, Shi H, Liu H, Zhou X. Biomechanical Analysis of Running in Shoes with Different Heel-to-Toe Drops. Applied Sciences. 2021; 11(24):12144. https://doi.org/10.3390/app112412144
[8] Zhang M, Zhou X, Zhang L, Liu H, Yu B. The effect of heel-to-toe drop of running shoes on patellofemoral joint stress during running. Gait Posture. 2022 Feb 13;93:230-234. doi: 10.1016/j.gaitpost.2022.02.008. Epub ahead of print. PMID: 35183841.
[9] Esculier, JF., Dubois, B., Dionne, C.E. et al. A consensus definition and rating scale for minimalist shoes. J Foot Ankle Res 8, 42 (2015). https://doi.org/10.1186/s13047-015-0094-5
