Discussion: Miles on shoes

How many miles should you run on a pair of running shoes before getting a new pair?

I'll be interested to see what others have to say about this, but depends on some variables including the weight of the runner and the materials used to make the shoe, particularly the sole. As the material in the sole breaks down you start to loose support and shock absorption. Don't know how much difference the surface type makes outside of tread wear.

Seems like the ranges I've seen run from 350-500 miles. On the lower end for heavier runners.

Pay attention to what your feet (knees?) are telling you. Unusual aches or pains might be a good indicator for a new pair.

I seem to get about 400 miles before I start to notice changes in how my shoes fit.

i think that it is between 350 and 500 miles, but that also depends on what surfaces you are running on, or how durable the shoes are. running on pavement wears a lot more out of a shoe than running on trails or grass.

Ok so i have about 200 i think on mine and almost all of that has been on pavement path/very compacted trail. The only real thing i have noticed so far is that i have to tie the shoes tighter to get the same kinda snug feel/support. My knees are bad anyway (bruised my left knee cap just over a year ago) so not sure how good of an indicator they are.

I retired my shoes after 300 miles and still lost the cartilage in my knee. Shoes are much easier to replace.

But 200 seems a bit on the low side, though, I'm not an expert. If it's an entry level pair of shoes, maybe 200 is the expected life span??? I start to phase in a new pair at around 300 (I'm at 340, just bought some last weekend).

As the shoes age, the uppers will stretch and the inserts will compress creating more room in the shoe.

It also depends on how much you run. The midsoles harden over time. After around 6 months, you've lost most of your cushioning, even if you haven't taken them out of the box. That's one reason you should buy shoes at a running store or from a reasonably high-volume mail order source. The pair you see discounted at Payless may look the same, but it's probably someone else's surplus and has been on the shelf for a while.

I get 400-500 out of road shoes, which is about 15 weeks of training depending on time of year. My trail shoes last much longer (calendar time) because I don't really care much about cushioning on the trail. I still usually destroy the uppers after less than 500 miles but, since I always rotate among two pairs of trail shoes, it takes the better part of a year to get that much distance on a single pair.

Huh? ebuckley, are you really claiming that the midsoles are made from a plastic that oxidizes or decomposes within a year or two? I find that surprising, to say the least.

I've never understood why there isn't a company out there that specializes in making shoes with more durable midsoles that last thousands of miles. It would be a niche company, but a lot of the runner's (as opposed to fashion) shoe companies are pretty niche anyway. (Equally, I've never understood whether this is a technical problem or an economic one.) Anyone know?

My road shoes which I use for everything are done by 400 miles pretty much every time.

Ok so some people are saying how long you have had the shoes and other are just saying distance. So most are saying distance so i'm going to go with that even though i have had my running shoes for almost a year now (didn't use them in the winter though really) that i've still got quite a few miles to put on them. Thats good news as i like my running shoes! although i'm still a little worried because i do feel like i'm starting to feel more of the pavement and such but maybe that is just me not used to running so much yet.

are you really claiming that the midsoles are made from a plastic that oxidizes or decomposes within a year or two?

Yeah, can we have a source for this stale shoes assertion?

Estimates on the shelf life seem to range from 6 months to 2 years with a year being the most common.

I think most midsoles are made from EVA foam which is a cross-linked co-polymer?.?. Haven't found any lit refs but I may not be looking in the right places. Any polymer chemists out there?

Distance based lit ref abstract. I don't have access to the whole paper. By 300 miles there seems to be a huge increase in stress on the plantar.

I guess I am the odd person who does not follow the rules. I get new shoes occasionally but continue to wear the old ones until they are completely worn out. By worn out, I mean the upper is trashed, the heel counter breaks, the sole wears thru in the forefoot, or the heel sole has worn so much it cant be built back up with a glue gun. I just alternate the new ones in with increasing frequency until they become the main shoes and the old ones are retired.

Looking at my shoe log: my primary running training shoes are 7 years old and have 856 recorded miles. I put in Sorbothane inserts for cushioning but the uppers are starting to go so they may be retried soon. My 2ndary training shoes are also 7 years old but only have 319 miles. My two pairs of racing shoes are 6 and 8 years old and have 409 and 351 miles.. My newest pairs of training shoes are 2.8 years and 4 months old and have a mere 269 and 14 miles on them.

Unlike many others, I have not had problems with injury from old shoes. I usually buy them off the discount rack and take anything that fits. The Sacauny Grid Shadows (with 856 miles) were an exception, I got them at a running store after consultation and fitting from the clerks.

are you really claiming that the midsoles are made from a plastic that oxidizes or decomposes within a year or two?

My first guess would be loss of plasticizer due to offgassing, but when I googled "EVA foam deterioration", I got this (pdf). It seems to say the primary issue is just the repeated damaged due to the force exerted by the feet (sorry, couldn't resist), although it also mentions a loss of the air in the foam and some other ideas.

If I read the paper right, it said the most rapid damage is when the shoes are first put into use, and that the later damage, while progressive, occurs at a slower rate.

Regarding your question about more durable midsoles---This article got me thinking about the Nike Air system. I always figured it was a marketing gimmick, but maybe it is a real attempt to improve upon straight-up EVA foam. I know the Air system doesn't like thorns, so it's definitely something for the road.

{edit} This pdf is the paper mentioned above in abstract form.

TimGood: I guess I am the odd person who does not follow the rules. I get new shoes occasionally but continue to wear the old ones until they are completely worn out. By worn out, I mean the upper is trashed, the heel counter breaks, the sole wears thru in the forefoot, or the heel sole has worn so much it cant be built back up with a glue gun.

Those are the shoes that, in their second lives, get worn with my snowshoes.

Since I'm somewhat injury prone my shoes last about 350 miles before I start developing aches and pains that would eventually lead to inuries... Thanks to Attackpoint I can track the miles on each pair of shoe that I have. Yet another reason this is such an awesome site!!

It's almost the exact opposite of whiskey, where the more rapid damage comes later on.

...I guess I am the odd person who does not follow the rules. I get new shoes occasionally but continue to wear the old ones until they are completely worn out....

I agree with TimGood. What's more, I don't really like a shoe until it has logged a couple hundred miles to pack down all that cushion.

I think a lot of the stuff you read about shoe replacement is an insideous campaign by the shoe companies. After all, in bike racing, you pay steep prices for equipment that is super-stiff and doesn't flex. This is because every bit of flex (or cushioning) decreases the amount of your energy that is transmitted to going fast.

Even tho I weigh over 200lbs, I prefer racing flats...old ones.

While I'm sure that shoe companies would love for you to replace your shoes often, I'm also sure that there's a noticeable change in support after a few hundred miles. Those who are blessed with sturdy mechanics can probably get away with running in anything... but those of whose feet are attached to our legs wrong (doctor's words, not mine) really benefit from all this fancy schmancy shoe stuff.

To keep this on track, I find a difference after ~300 miles on road shoes, at which point the shoes are demoted to secondary status in the rotation. I'll still use them, but not for road runs of any good length. I'll use them for shorter runs, runs in cruddy weather, gym work, recreational team sport games, whatever.

I get new shoes when the old ones pretty obviously suck. Like when they have holes in them. And I even have flat feet. But I do almost no running on pavement. That's what unicycles are for.

Clark weighs over 200 lbs.?!! Really? Did marriage cause you to bulk up or sumpin?