When do I replace my running shoes?

Posted by Rick Cleary

The experts say that you should replace your running shoes every 300 to 500 miles.  But there are so many factors that go into the proper time to replace your shoes.  That is why the Shoe Odometer team developed the Shoe Odometer Calculator.  We factored in the main components of shoe wear into this Calculator: weight of the user and the type of past wear on old shoes.  There are other factors such as type of shoe (trainer, light weight trainer, racing flat, motion control, ……). We did did not include all factors into the calculator to keep the calculator user friendly.  The Calculator is a good starting point.  Once you start using your Shoe Odometer you can adjust your Shoe Odometer to your own personal number.  Our goal was to make life and running easier.

If you are like me, when you are thinking of buying something it’s hard to listen to the person trying to make the sale.  So instead trying to convince you that having the proper “shoe ride” is important to keeping you running injury free, I’ve included several links below.  Good reading and know the the Shoe Odometer is the easiest way on the planet to monitor your shoe wear.

Runner’s World: Your Tread Life

Once you purchase shoes with the right fit, you then need to maintain them and replace them when they’re worn out. The average life of most running shoes is 350-500 miles, but if you’re a heavier or taller runner, or if your gait isn’t smooth, you may need new shoes sooner. Even you light-footed types should know that shoe materials deteriorate fairly quickly; after just 100 miles, a running shoe loses some of its shock-absorption.

After a wet run, many runners throw their shoes next to a heater or put them in direct sunlight to dry. Bad move. Over time, this will cause your shoes to shrink. Nor should you stash your running shoes in an unheated garage or on the outside porch in cold weather. Cold temperatures make the midsoles harder and less cushiony. It’s best to store your running shoes in the house away from the heat after removing insoles or orthotics.

A tip: If you run every day, invest in multiple pairs of running shoes so you always have a dry pair. And pay attention to the condition of your shoes, especially the midsole, the section between the outer tread and the “upper” that your foot fits into. If the midsole is compressed, brittle or feels unusually hard, it’s probably worn out. If so, don’t use the shoes for running. Gardening maybe, but not running.

Run the Planet: Why Do We Need To Replace Our Shoes So Often?

Even with all the new technology and research in running shoes, why do the experts still recommend that we replace our shoes every five hundred miles? It seems to me that as the price of shoes increase, their life span should increase as well - Everlasting Shoes

Dear Shoes: There are two reasons why the experts recommend that you replace your running shoes every five hundred miles: (1) The Earth is mostly very hard and (2) your body is mostly very soft. Were it not for these two properties, a runners need to replace their running shoes would be of minimal importance. Imagine a world where the streets were paved with diamonds, our running shoes were constructed of high gauge iron, and our bodies were made of reinforced steel. Ignoring, for a moment, the numerous ill effects on the universe within such a world, we would find that your desires for an ever lasting shoe would be more plausible.

When you consider the physical interaction between your malleable body and the Earths solid hardness, it is not difficult to imagine why your rubber sole shoes wear down approaching the five hundred mile mark of repeated pounding. With each crushing stomp of pronation your soft, rubber-shoe sole makes a sub-atomic physical bond with the road (literally becoming “one” with the planet). This interaction is called friction and it is the adversary of runners world-wide.

It is friction that we curse when suffering from Chrondromalacia Patella, it is friction we despise when the first symptom of a stress fracture is found in a callus formation on the outer edge of our tibias. Friction is the enemy, and the source of all our woes.

As friction is our adversary, so too is gravity: that downward sucking force that cements us to our planets surface despite all efforts to remain airborne through the efforts of running. Future Lunar or Martian marathoners will laugh at us Earth-bound runners as they traverse their lightened loads across the “magnificent desolation” of their worlds. We are cursed to live upon the third planet from our star, and remain subjected to the 32 meters/second acceleration that bonds us to our own spinning globe.

With each mile that you run, your running shoes wear down in a way closely related to your bio-mechanics. Those who over-pronate tend to have the inner soles of their shoes “scraped away”, while under-pronators have the outer soles depleted. Flat footed “neutral” runners find that their soles wear down over the middle arch and “ball” of the foot. In every case, it is the constant pounding friction that demands such replacement. The “five hundred mile” limit is more of a guideline than it is a strict rule. With some poorly constructed shoes, the limit will be closer to two hundred miles.

Failure to replace older, worn-out shoes will lead to a running injury. Remember that the Earth is unlikely to yield to the pounding force you place upon it with each run and your body’s mechanical motion is likewise unlikely to change. Thus if you are running with a shoe that is unable to compensate for your form, weight and persistence, it will be your body that succumbs to the uncorrected stress. The results could be painful and nasty.

Many runners chose to purchase an extra pair of shoes, which they “alternate” in use, to prolong the need to purchase new shoes with increased frequency. I typically purchase two to three pairs each year, spaced out every four months

ATLANTA, Georgia (CNN) – — Julie Beverly runs about 20 miles a week. While her workouts are helping to tone her body, they’re also wearing down the soles of her sneakers. “The shoes are starting to bow on the sides because they’re so old,” says Beverly. “Actually, they’re making the back of my ankle hurt.”

Beverly isn’t alone in complaining of foot, heel or leg pain. Atlanta, Georgia, podiatrist Perry Julien says, “We estimate that 20 percent of the people that come into our office with an injury are there because of their shoes. Either they’re worn out or they’re just incorrect for their foot type.”

Running shoes don’t last forever, the doctor says. He recommends that athletes keep track of their mileage and replace their workout shoes every 250 to 500 miles. For someone who runs 20 miles a week, that could mean new shoes as often as every three months, but probably about every six months for sure.

Dr. Julien also recommends that people mark their shoes with the date of purchase to keep precise track of the age. “A date or knowing how much you run on it is better than looking at them,” he says.

“Often times when a shoe wears down, it wears down in the mid-sole, and you can’t see that wear,” he says, “but then you lose the support and the cushioning.”

Julien tells his patients to buy their running shoes from a store with experienced sales personnel. They can help determine the right style of shoe for your foot.