Worn-Out Shoes: Signs It's Time for a New Pair

Shoes rarely fall apart all at once. The tread fades a little at a time, the foam slowly flattens, and the back of the heel gets softer. Because it happens so gradually, it's easy to keep wearing a pair long after it has stopped doing its job. Sometimes people notice a new ache first and only then look at their shoes.

This guide explains how shoes wear out and which parts go first. We cover the signs that a pair is done, and why a single mileage rule doesn't fit everyone. We also explain how to make shoes last, and when shoes that wear out early or unevenly point to a foot problem.

What Wears Out First

A shoe has four main parts. The outsole is the rubber tread on the bottom. The midsole is the foam layer that does most of the cushioning. The upper is the fabric or leather that holds your foot, and the heel counter is the stiff cup at the back of it. Each part wears at its own pace.

The midsole can lose much of its cushioning while the tread still looks fine. Cook and colleagues (1985) tested running shoes on a machine that copied the pounding of a heel, mile after mile. The shoes lost a good share of their shock absorption over the first few hundred miles. Expensive and cheap models lost cushioning at about the same rate. Shoes worn by real runners lost less than the machine-tested ones, but the drop was still marked. Shoes have changed since then, and newer foams may age differently.

The damage shows up under the foot, too. Verdejo and Mills (2004) measured pressure under the heel in running shoes as they aged. In that study, peak pressure under the heel had roughly doubled after about 500 kilometers of running. That study also found real damage in the foam under a microscope by 750 kilometers.

Your body adjusts as the shoe wears. Kong and colleagues (2009) had 24 runners log 200 miles in new shoes. As the cushioning wore down, the runners changed the way they ran to keep the impact the same. The type of cushioning made no difference.

Why There's No Magic Number

You've probably heard a rule like "replace your running shoes every few hundred miles." It's a reasonable rough guide, but it doesn't fit everyone. The foam itself matters. Wang and colleagues (2012) gave runners shoes that were identical except for the midsole foam. The different foams held their cushioning in different ways over the same distance.

The rest depends on you. Body weight, the surfaces you walk on, how you land and how many hours a day you spend on your feet all change how a pair ages. A nurse on concrete floors wears out shoes differently from a weekend walker on trails. That's why the signs below matter more than the calendar.

Signs Your Shoes Are Done

Check your shoes every month or so. Clinicians who assess footwear look at many of the same things, including wear, cushioning and how firm the heel counter is (Barton and colleagues, 2009; Menz and Sherrington, 2000).

• The midsole is creased or squashed. Deep wrinkles in the foam, or one side lower than the other, are signs the cushioning has worn down.
• The tread is worn smooth, especially at the heel, or worn through to the foam.
• The heel counter is soft. If you can fold it flat with your thumb, it no longer holds your heel.
• The shoe tilts. Set the pair on a table and look from behind. A shoe that leans to one side has broken down.
• The insole is flat or shows a deep print of your foot.
• The upper is torn, or a toe is poking through.
• Old aches come back, or your feet, knees or back feel sore after a walk that used to be easy. Worn shoes are one thing to check.

Worn Shoes, Slips and Falls

A worn sole loses its grip. Hemler and colleagues (2019) wore down the tread of slip-resistant work shoes in stages, using a lab machine. Once the smooth patch at the heel grew past a certain size, the shoes lost traction on a slick floor. That matters for anyone who works on wet or greasy floors.

Shoe features matter for older adults, too. Sherrington and Menz (2003) looked at the shoes 95 older adults wore when they fell and broke a hip. In that study, three out of four wore shoes with at least one feature thought to be unsafe. The most common were no laces or straps, a floppy heel counter and a sole that bent too easily. The study had no comparison group, so it can't show the shoes caused the falls. A review of footwear and falls advised older people to wear shoes with low heels and firm, slip-resistant soles, indoors and out (Menant and colleagues, 2008). Our post on preventing falls covers more.

How to Make a Pair Last

• Rotate two pairs. It spreads the wear across both. Malisoux and colleagues (2015) followed 264 recreational runners for several months. The ones who switched between more than one pair of running shoes had a lower risk of running injuries. That study looked at injuries, not at how long shoes last.
• Use each shoe for its job. Running shoes are built for forward motion. Court sports, yard work and long shifts on concrete each wear a shoe in different ways.
• Untie your laces to take shoes off. Stepping on the back to kick them off breaks down the heel counter.
• Keep them away from heat. A clothes dryer or a hot car can weaken the glue and the foam.
• Replace a worn insole. A new insole can freshen up a shoe that is otherwise in good shape. It can't bring back a crushed midsole.

When Early or Uneven Wear Points to a Foot Problem

Sometimes the shoe isn't the problem. Say one spot wears through long before the rest of the sole, or one shoe wears out much earlier than the other. Then the pattern is telling you something about how you walk. Our guides explain the common patterns.

• Shoe wear patterns and what they mean
• Shoes that wear out on the outside heel
• Shoes that wear on the inside edge
• Wear under the ball of the foot and the toes

Buying new shoes over and over won't fix a pattern like that. If your feet hurt as well, it's worth an exam. After an exam, a good store-bought insert is often a reasonable first step. For heel pain, store-bought insoles have done about as well as custom ones in trials (Whittaker and colleagues, 2018). In trials of active people, contoured foot orthoses lowered the overall rate of injuries and of stress fractures, though not of soft-tissue injuries. Soft shock-absorbing insoles did not lower injury rates (Bonanno and colleagues, 2017).

A custom functional orthotic is made from an impression of your feet. It makes sense when pain keeps coming back, your foot shape doesn't fit store-bought inserts, or the exam shows a clear mechanical problem. Our guide to how custom orthotics work explains the details. Orthotics wear, too. The top cover can usually be replaced when it wears out, so bring them to your checkups. If you have numbness or diabetes, any insert needs a careful fit and close skin checks.

When to See a Podiatrist

Make an appointment if any of these apply.

• Pain that started as your shoes wore down and doesn't settle in a new pair.
• One shoe wearing out much earlier than the other, or one spot wearing through first.
• Slips, trips or a fall, especially if you're an older adult.
• Calluses, blisters or color changes on a foot that is numb.

One practical tip: don't throw out your old pair before your visit. Worn shoes show the pattern far better than new ones. Bring them, along with any insoles or orthotics. Dr. Patish will look at the wear and examine your feet, then recommend what fits, whether that's new shoes, exercises, a store-bought insert or a custom orthotic. You can request a visit online.