Pronation Wear on Shoes

During walking and running, your foot will naturally roll inward, a motion known as pronation. The pattern of pronation that is shown in your gait can be neutral, overpronated, or supinated (underpronation). Overpronation is a condition that happens when the way you walk causes your arches to become flatter over time, which causes tension in the muscles of your feet and legs. There is a correlation between the stresses caused by overpronating or supinating and an increased risk of injuries.

If you are an overpronator, it is possible that you will benefit from wearing motion-control shoes and orthotics. On the other hand, people who supinate should look for shoes that are flexible and cushioned. Acquaint yourself with these walking patterns and the corrective measures you can take if you find that they are contributing to your discomfort (many people over- or under-pronate with no ill effects).

If you’re a runner or just like to walk around a lot, then you’ve probably noticed that your shoes have worn unevenly on the bottom. This is called pronation wear, and it’s caused by the way you walk. The front of your foot rolls inward when you take a step, so when you’re walking or running, this can cause one side of your shoe to wear down more than the other.

Some people are more prone to pronation than others, but anyone can experience it over time if they’re not wearing the right kind of shoe for their gait.

This is why it’s important to get fitted for running shoes at places like Runner’s World or Nike. When these stores measure your feet and recommend specific models for your pronation type, they’ll usually give you a discount too!

Pronation wear on shoes

What Wear Patterns Mean for Walking Shoes

What your walking shoes look like after some wear—think holes, minor tears, and smoothed-out soles—can tell you a lot about both your shoes and your walking form, or gait. You can examine wear patterns on different parts of your shoes to learn more about your walking mechanics and form.

Types of Gait Patterns

In general, there are three types of gait patterns:

• Normal: Pronation is the natural movement of your foot as you walk or run, with your foot rolling in slightly with each step. 
• Overpronation: Here, the ankle rolls more inward and downward with each step and continues that motion when the toes should start to push off. Common in those with flat feet, overpronation creates a twisting motion with the toes doing most of the work, which can be associated with knee pain and shin splints.¹
• Underpronation: Also called supination, this gait causes your foot to roll outward with each step, putting more pressure on the outside edge of your foot and small toes. It’s most common in people with high, rigid arches and can be associated with iliotibial (IT) band syndrome and stress fractures.²

According to the American Academy of Podiatric Sports Medicine, check your athletic shoes after a total of 300 to 500 miles of running or walking, or 45 to 60 hours of sports, such as basketball, dance, or tennis.³ After that time, your shoes will have endured approximately one million steps and may have lost their cushioning and support.

Shoe wear patterns can help you decide whether you need to correct any issues, if your feet are being adequately supported, or if it’s time to go shopping for a replacement pair. And keep in mind that even a shoe that appears relatively new could be hiding a worn-out sole.

Heels

The shoe on the left shows a normal shoe wear pattern after 350 miles. The shoe on the right is the same model and the same user. But the shoe on the right has only been worn for 100 miles.

This depicts a normal shoe wear pattern for a person with a neutral gait, who neither overpronates nor supinates. It rolls through the step from heel strike to push off with the big toe in a straight line. You can see the wear at the toe and at the heel.

Heel Wear Patterns

Use this reference when checking out your own shoes for heel wear patterns:

• A normal, neutral gait will see worn tread at the heel, especially toward the outside heel, as walkers strike with the heel at the beginning of each step. They will also see worn tread below the first and second toe, as they push off with the toe after rolling through a step.
• Overpronators will see more heel wear in the middle of the heel and perhaps even toward the inner edge of the heel (the big toe side). Their shoes may even tilt inward when placed on a flat surface.
• Supinators or underpronators will see treadwear all along the outer edge of the heel. When placed on a flat surface, their worn shoes may tilt outward.

Soles

Worn soles signify that you should replace your sneakers.⁴ Shoes are often designed to show this wear on the sole with a change of color, which can help persuade you that it is time to replace the shoes. The shoe pictured on the left has logged about 350 miles and is showing wear on the sole near the big toe.

Sole Wear Patterns

These signs can help you determine what your sole wear patterns may mean:

• A neutral gait would show wear under the big toe. Neutral-gait walkers naturally push off with the first toe without excessive rotation during the stride.
• An overpronator would see the worn off spot even more toward the big toe side of the sole.
• A supinator shows wear is mostly along the outside edge of the shoe, closer to the little toe. The change in color shows a lot of wear on the heel. At the toe, you can see almost no wear on the inside to the middle portion of the sole.

 Buying Walking Shoes? Get the Correct Fit

Sole Cushioning

The shoe pictured on the left has endured about 350 miles of walking, which equates to about 770,000 steps. It’s clear there’s already a significant loss of cushioning. Though this is a bit more difficult to assess than other wear patterns, inspect your shoes for different patterns of wrinkles.

Sole Wrinkle Wear Patterns

• Compression lines signify that the shoe is aging and losing its ability to cushion and support. (If you were switching back and forth from wearing the older shoe to wearing a fresh pair of shoes, you could probably feel the difference in cushioning.)
• Wrinkles are developing in the indented area in the heel of the shoe on the left, a sign that the shoe isn’t springing back from the compression it uses to cushion each step

Walkers who are on the heavier side will likely need to replace their shoes more often than is typically recommended due to faster degradation of sole cushioning.

 When Should You Replace Your Walking Shoes?

Exterior Soles

With each step, your shoes break down little by little. The materials used in the sole and heel of your walking shoes have a limited lifespan. Shoes even age when sitting on the shelf unworn and will continue to break down once you start wearing them.

Small cracks and wrinkles can be seen in the exterior heel of the walking shoe pictured. These are caused by the constant compression with each step as well as the aging of the materials. As the shoe loses its ability to spring back with each step, it has less ability to cushion. You may start feeling more fatigue in your legs and feet after a long walk.

Shoe Interior

The shoe pictured is breaking down from the inside out. Not only do the outside of shoes reflect wear and tear, but you also may be creating holes in the interior of your shoe. This walker has worn through the first layer of fabric at the bottom of his ankle as the bone rubs against the side of the shoe.

Interior Wear Patterns

Take the time to look inside your shoe for the following:

• A hole may occur in a spot where you developed a blister or hot spot. The rubbing of your foot against the shoe creates friction that can damage your skin as well as the shoe fabric.
• Interior holes are also a sign that your shoes may be too tight and you need bigger shoes, as feet naturally swell while walking. This is also why when buying shoes, it’s better to shop in the afternoon when your feet increase in size to ensure a better fit.²

In the case of a hole near the heel, it’s important to learn how to lace your shoes to keep your heel from sliding forward in your shoe, especially when walking downhill.

 Do You Really Need Bigger Walking Shoes?

Shoe Exterior

Constant pressure and rubbing from your big toe or your little toe may cause small holes to appear on the tops of your shoes. Worn-out uppers (the fabric covering the toe box) are a sure signifier that it’s time to replace your sneakers. Other holes may appear around the ankle cuff of the shoe due to ankle friction while walking. When you see a hole, it’s time to replace your shoes.

Should You Wash Your Shoes?

It is tempting to want to wash dirty shoes, but soap and heat can break down the glue holding the shoe together. If you must wash your shoes, wash them by hand with mild soap and allow them to air dry. Washing and/or drying shoes in a clothes washer or dryer can shorten their lifespan. If your sneakers get wet, stuff newspapers into your shoes to soak up excess moisture.

lateral wear on shoes

As people transition through their stride and get ready to push off the ground, they can create some extra wear at the forefoot, or front of the shoe. This can be in the center, outer, or inner side, depending on how much pressure the runner puts through their toe-off, what available flexibility/mobility they have, and what muscles and movements they’re using to transition over their toes. There’s a great deal of variety that occurs here.

There’s even variety in wear patterns between the feet of a single person. Humans are asymmetrical. The heart is off to one side, as is the liver. Just as asymmetry is present in the rest of the body, a little asymmetry in wear patterns is normal. A majority of people have a dominant side of their body, have different length feet and lower limbs, and even different spinal curves.

MATTHEW KLEIN

What do research and experts say?

Here’s the main thing I want you to take away from this article: There’s no evidence that wear patterns mean anything. No studies have come out that associate certain wear patterns with certain injuries. Looking at outsole patterns isn’t a valid or reliable method for diagnosing or assessing problems. Doing so is like trying to look through a window from a half-mile-long yard to see what’s going on inside a house. You might be able to see the window, but you really have no idea what’s happening in the house.

The only valid and reliable ways to assess someone’s injury risk or whether they have a certain pathology is to assess how they move (often by performing a camera-assisted gait analysis), test the area they’re complaining about, test their strength, test their range of motion, test their mobility, take a thorough history, ask about their training, and actually look at the person! Only then will you have an idea of what’s truly going on and be able to make some conclusions.

The other problem with divining from wear patterns is that there’s so much variation among runners. Two individuals may have the exact same wear pattern but have completely different movement patterns. Another two individuals may have different wear patterns but have similar looking running styles. There are so many factors that go into this: how hard you hit the ground, what muscles you’re using to absorb shock and propel yourself, whether you bounce off the ground or grind into it, how much mobility you have at your feet, knees, hips and spine, and enough other variables that if I keep listing them you’ll stop reading this article. Only after assessing all of them can a qualified person make conclusions. That’s a massive difference from making universal pronouncements on the basis of a single piece of shoddy, unreliable, and unvalidated information.

More problems with basing conclusions on wear patterns include that they can be different between running shoes, they’ll change over time, and they may differ depending on what surface you run on. Different shoes have different levels of softness or firmness, different heel-toe offsets, different levels of durability, and different areas of durability. These also change as running companies continually modify their shoes. Changing your routes may influence outsole wear as different surfaces, road angles and more may influence wear. This creates even more confounding factors that make wear patterns unreliable. Seeing different wear patterns with different shoes or over time is normal.

Again, no wear pattern has ever been linked to a pathology. Even those who argue that certain wear patterns mean you pronate or supinate haven’t figured out that those terms define normal motion and, based on clinical research, have been shown to protect against many types of bone stress injuries.

Having a certain or unique wear pattern doesn’t mean you are going to have problems. Your time would be much better spent assessing your training routine, figuring out what weaknesses you might need to address, or going to someone who can help you determine the answers to one or both of those matters. Strength training and smart training plans are two of the few validated things known to reduce injury risks in runners.

Do wear patterns tell you anything?

The one thing wear patterns can tell you is when you might need to get a new pair of shoes. While certain patterns are unique to each person and don’t tell us much about the runner, wear does give us an idea about how broken down the shoe is. Each person will wear their own unique movement pattern into the shoe. The more the shoe gets worn down, the more those movement patterns will be exaggerated. Any movement faults may become more extreme as the shoe starts to break down.