Zach Friedenreich, PT, DPT
Physical Therapist, New York City
Spring marathon training season is upon us! Whether you are training for a marathon, or have a goal for the New Year of picking up running, you are likely looking to purchase one of the top brand’s latest and greatest running shoes to carry you through the upcoming training.
When it comes to running shoes, we are often asked one of two questions:
- Which type of running shoe is correct for me?
- Which brand should I be looking at?
If you have ever asked or wondered about either of these questions, I am here to provide some clarity and, hopefully, simplify the process for you.
Traditionally, most runners and medical professionals believe that there is a “perfect” running shoe that provides an individual with optimal running mechanics. This includes shoe characteristics like greater support to eliminate pronation, or flattening out of the foot, and cushioning designs that lessen the impact forces while running. Both of these things, pronation and impact forces, were thought to be primary contributors to running related injuries in the recent past. It was believed that mitigating these variables, and these variables alone, was the key to preventing such injuries. If you weren’t wearing shoes that accomplished these two things, you were doing it wrong.
Similarly, there was, and still is depending on who you talk to, a push for the utilization of “minimalist” running shoes. Minimalist running shoes tend to have a smaller amount of cushioning and a lower offset, which is the difference in the height of the shoe’s heel and the height of the shoe’s forefoot, to mimic running barefoot. The thought process behind using this category of shoes is that there is a “best” part of the foot to make contact with the ground with each step. The goal is to promote landing further forward on the foot, often referred to as a forefoot strike, in order to reduce the impact forces with each step. Additionally, it is thought that wearing minimalist shoes encouraged a higher cadence, which is defined as the number of steps taken per minute of running. Higher cadences were also thought to reduce the impact forces that the body’s muscles, tendons, and joints would feel while running. It is important to note that in certain situations there is some benefit to increasing your cadence, which we will discuss later in this blog post, but it does not require the use of minimalist shoes.
Today, based on the evidence that we have available to us, we know that foot pronation and impact forces are not strong predictors of running related injuries. In fact, interestingly enough, we know that the frequency of running related injuries has remained relatively unchanged over the last 40 years despite a sharp increase in the overall number of runners. Why might this be?1
Let Comfort Be Your Guiding Light
One of the reasons that may explain why the frequency of running related injuries has not changed significantly is a concept called the “Comfort Filter”. In simple terms, the comfort filter asserts that an athlete chooses the most comfortable product for themselves when selecting running shoes. Each individual prioritizes certain shoe characteristics because they create the most comfortable environment for them while running. Some people prefer a shoe that has more support and limits pronation, some prefer a shoe with little to no support at all. At the end of the day, the reason behind each person’s choice is the greatest level of comfort.
The reason that this concept of the comfort filter is so important is that we now know through research that comfortable shoe conditions are strongly associated with a lower rate of injury compared with shoe conditions that are less comfortable. Neither condition is fundamentally “correct”, but selecting the one that feels most comfortable on an individual basis automatically reduces risk for running related injuries. Since the majority of runners have likely been avoiding uncomfortable, potentially injury producing, running shoes from the start, the concept of the comfort filter may explain the lack of change in running injury frequency. Not to mention, It is also a solid reason to continue abiding by the comfort filter when choosing a new pair of running shoes (1).
Using Multiple Running Shoes
Besides comfort being protective against running related injuries, recent evidence has also shown that alternating between two or more different pairs of running shoes, both of which are subjectively comfortable, can reduce risk of injury by up to 39%. Although I wouldn’t necessarily advocate for jumping to purchase multiple pairs of running shoes if you are a novice runner, many experienced runners are already tapping into this risk reduction. Often, runners choose different shoe variations based on the goal of their workout on a given day. For example, a runner may choose “Shoe A” for a tempo or speed workout, but may feel more comfortable in “Shoe B” for their longer, slower run on the weekend (2).
Using two or more different shoes in your training program may provide some variability in the load that your body is experiencing while running. This variability not only protects the bones, muscles, and tendons from repetitive-stress type injuries, but also provides different stresses for your body to adapt to and become more resilient overall.
Heel-Toe Offset in Running Shoes
Finally, evidence has shown us that a running shoe’s offset has no association to running injury risk. Therefore, it is OKAY to run in low, medium, or highly cushioned shoes of various offsets. Again, all this really tells us is that it is most important to refer back to the comfort filter when making your decision. Whatever shoe feels the best, which may be a minimalist shoe for some and a maximalist shoe for others, is likely the shoe that will put you in a position for success as it relates to reducing your chance of injury (3).
Earlier, I mentioned that in certain scenarios it may be beneficial to increase the cadence at which you run. More specifically, if you are experiencing some sort of lower body pain (hip, knee, shin, ankle, foot), increasing your cadence by 5-10% from your usual average may help to alleviate these symptoms. In addition, gradually increasing your cadence may help to limit these sorts of symptoms from returning in the future. Keep in mind that changing your cadence too greatly or too suddenly may actually place you at a higher risk for developing some aches and pains. You must ensure that you make any changes to your running form in a progressive, gradual manner for the best results. It is best to do so under the expert guidance of a running coach or physical therapist.4
Based on the evidence that we now have available to us, the process of choosing the “correct” running shoe for the purposes of reducing your injury risk is much less complicated than we once believed. Hopefully, the major takeaway from this blog post is that you should allow comfort to guide you when choosing your next running shoe. If you are an experienced runner and have found a shoe, or shoes, that is/are comfortable for you, stick with them. If you are a new runner and are caught up in the seemingly endless number of brands and marketing tactics, my advice would be to try on as many shoes as possible before making your decision. Ideally, try and find a running store that will allow you to try running with them in person. This eliminates the guesswork as to what you feel fits your foot best when you finally put rubber to pavement.
- Nigg BM, Baltich J, Hoerzer S, et al. Running shoes and running injuries: mythbusting and a proposal for two new paradigms: ‘preferred movement path’ and ‘comfort filter’. Br J Sports Med. 2015;49:1290–1294.
- Malisoux L, Ramesh J, Mann R, et al. Can parallel use of different running shoes decrease running-related injury risk?. Scand J Med Sci Sports. 2015: 25: 110–115.
- Malisoux L, Chambon N, Urhausen A, et al. Influence of the Heel-to-Toe Drop of Standard Cushioned Running Shoes on Injury Risk in Leisure-Time Runners: A Randomized Controlled Trial With 6-Month Follow-up. The American Journal of Sports Medicine. 2016;44(11):2933-2940.
- Bonacci J, Hall M, Fox A, et al. The influence of cadence and shoes on patellofemoral joint kinetics in runners with patellofemoral pain. Journal of Science and Medicine in Sport. 2018;21:574–578.