Some runners like to hold onto their old running shoes for sentimental reasons. Perhaps they were the shoes you wore for your very first 5k or when you were training after the delivery of your firstborn while logging miles pushing a jogging stroller.
Other runners like to donate their old running shoes to charities that upcycle lightly-used sneakers to less fortunate individuals around the world.
However you celebrate the end of the life of your old running shoes, there’s something you should do before you stash them in the back of your closet, toss them away, or donate them: take a few minutes to examine the soles of your sneakers.
The wear pattern etched into the soles of your running shoes is more than just evidence of the hundreds of miles or kilometers you logged in your beloved pair of kicks.
We will cover:
- What Is a Shoe Wear Pattern?
- What Can Wear On Running Shoes Tell You About Your Gait?
- Common Wear Patterns On Running Shoes
- Cautions With Relying on Wear Patterns
Grab your shoes, and let’s dive in!
What Is a Shoe Wear Pattern?
The wear pattern on your running shoes refers to the way in which the appearance of the sole has changed since the shoes were brand new.
As long as your running shoes have been used and aren’t right out of the box, if you take them off and flip them over to look at the sole, you’ll notice some wearing away of the rubber outsole.
As you wear your shoes, the friction and pressure between the sole of the shoe and the surface you’re running on (road, track, treadmill, trail, etc.) compresses and wears away some of the outsole material, shaving it down from its original form.
The wear on running shoes basically tells you what areas of your shoes are sustaining the most ground reaction forces when your foot comes into contact with the ground, as well as the areas on the shoe (and foot) that you’re pushing off with.
In this way, examining the wear on running shoes can elucidate information about gait pattern, and can help you identify imbalances and abnormalities.
With that said, examining your wear pattern in isolation can’t conclusively determine your risk of any specific injuries or gait abnormalities.
The wear pattern also depends on the materials and quality of the construction of the shoes, wear from ground contact and wear associated with push-off.
What Can Wear On Running Shoes Tell You About Your Gait?
- Asymmetries between your right and left sides
- Degree of pronation (are you overpronating, supinating, or do you have a neutral gait?)
- Your foot strike pattern (whether you land on your rearfoot or heel, midfoot, forefoot, or ball of your foot)
Note that each of these pieces of information can potentially provide insight into your risk of injuries, the best type of running shoes for your gait (neutral or cushioned shoes, stability shoes, or motion control shoes), whether you should consider orthotics or insoles for your running shoes, and potential muscular imbalances contributing to gait abnormalities.
Let’s examine common wear on running shoes and what it can indicate:
Wear Patterns On Running Shoes
Wear Across the Entire Heel or the Outside Edge of the Heel
Prominent wear along the lateral edge of the posterior part of the shoe (towards the outside edge under the heel) is indicative of heel striking.
The entire back edge or posterior region of the shoe may also be worn, but look specifically at the outer edge for a more definitive clue of heel striking.
Runners who heel strike tend to land with their foot in an inverted foot position because this gives the tibialis posterior muscle more room to eccentrically absorb the force that occurs during normal pronation.
This is why you’ll see wear on the outer back edge of the shoe.
If you are heel-striking, there’s a good chance you’re overstriding.
Overstriding occurs when you extend your leg too far ahead of your body. This positions your center of mass behind the knee, which, in turn, can lead to heel striking and increases the risk of injury.
Overstriding and heel striking can not only increase your risk of injuries but compromise your forward momentum as well.
One way to combat overstriding or heel striking is to try a running shoe with a lower heel-toe drop.
You can also try increasing your cadence, which can force you to use shorter strides.
Wear On the Inside or Inner Edge of the Heel
Wear on the medial or inside portion of the heel is indicative of overpronation, which means that your foot is collapsing at the arch and rolling inward excessively when you land.
Overpronation can increase the risk of injuries and is often associated with flat feet or low arches.
If you’re not already in a stability or motion control shoe, you will find more support in this type of shoe.
Insoles or orthotics may also help hold your foot in the proper position and maintain the integrity of your arch.
Wear On the Lateral Midsole
Wear on the lateral midsole of the shoe (the outer edge somewhere between the region of the foot where the arch is and the ball of the foot but on the outside) indicates that you’re landing on your midfoot or forefoot.
Midfoot striking is ideal, and most runners who have this foot strike pattern at ground contact land on the outer aspect of the foot and then roll inward towards the arch to absorb the impact of landing.
In a neutral gait, you land on the outer part of the midfoot, and then the foot rolls inward to the arch to absorb the landing, and then your weight transitions toward your forefoot, where you push off with your big toe since it is the strongest toe.
Therefore, if you have a neutral gait, you’ll have wear on the lateral midfoot, some on the medial midfoot, and wear under the medial forefoot and toe under your big toe area.
Wear On the Outer Edge of the Forefoot
Excessive wear on the lateral forefoot (outside edge of the toe box region) usually indicates that you’re supinating or inverting your foot excessively at push-off.
Rather than pushing off with your big toe, which is the strongest toe, you’re putting the work of propulsion on your lesser toes.
Supination at toe-off can be caused by weakness in the fibularis longus, a bunion or pain in the first metatarsophalangeal joint (big toe), or high, stiff arches.
This wear pattern can also be due to excessive tightness of the calves or the posterior tibialis muscle.
The problem with this landing excessively on the lateral edge of the sole and pushing off with the lateral toes is that you’re not taking advantage of the natural shock absorption of the arch.
Excessive Wear Along the Medial Forefoot
If you notice prominent wear along the medial forefoot, your forefoot may be everting or pronating at toe-off.
This can be caused by weakness in the posterior tibialis muscle or the fibularis longus muscle.
This push-off pattern of loading can increase the risk of bunions.
Wear Centered on the Forefoot of the Shoe
If there’s significant wear on the forefoot region of the shoe without much wear elsewhere, you’re a forefoot striker.
Cautions With Relying on Wear Patterns
Wear on running shoes is really only a piece of the puzzle.
It needs to be considered in the contact of the shape and structure of the foot itself, your running gait, the type of shoes you’re wearing, and injury history, among other factors.
Wear patterns can also be affected by the surface you run on.
Additionally, running on a treadmill is much more repetitive than running on a road or trail because the treadmill belt is the same exact surface over and over.
For example, if you habitually run against traffic on a road that’s sloped or cambered from left to right such that the right side of the road is higher than the left side, you’ll see more wear on the left shoe because this side is absorbing more weight than the right side.
Wear on running shoes also depends on the construction of the shoe itself.
The firmness versus softness level of the outsole and midsole in different running shoes can vary, as can the durability of the materials used.
Another key factor of the running shoe is the heel-toe offset, also referred to as the heel drop, which is the difference in height between the heel of the shoe and the forefoot area.
A shoe with a higher heel-toe drop is more likely to have evidence of wear on the heel because the heel is closer to the ground relative to the toe.
This, in turn, can promote rearfoot striking, which isn’t necessarily ideal, but it can also just be a product of the geometry of your footwear rather than your biomechanics.
Remember, when you’re about to retire an old pair of running shoes, take a look at the wear pattern, but don’t put all your stock in what you see-–wear on running shoes is only part of the picture of your gait.