The first company that comes up with a shoe design where the shoe turns blue when the cushioning has deteriorated beyond a certain point will make a fortune!! You heard it here first!!!
As mentioned above, there are several factors that affect how long the cushioning will last:
1. How heavy on your feet you are (not necessarily how heavy you are)
2. If you wear the shoes every day the cushioning will wear out quicker (thats why people advise rotating 2 pairs). Daft as it sounds, the EVA (foam) has a certain amount of bounce/elasticity so if the longer you leave it before you wear them again, the more the shoe will 'recover'.
3. The surfaces you run on. Softer surfaces will mean the shoe lasts longer

The standard figure for how long the shoe lasts is anywhere between 500-800 miles, depending on the above factors. Some people are lucky enough to have good biomechanics which means their shoes last longer, some are not. Forefoot strikers tend to wear shoes with minimal cushioning but don't wear them out as quickly, but that style does not suit everyone.

Apart from keeping an eye out for aches and pains/niggles that you don't normally get, there is no one rule that tells you when to change shoes. Have a look at the foam midsole and see if you can see any horizontal creases. The more of those there are, the more knackered (technical term) the shoe is!!

Hope that helps?

I just bought another bargain pair of Asics to keep under my bed until my current pair wear out (at the price would have been silly not to get them now). The Asics are exactly the same model as my current pair, so will be interesting to compare them in a few more months. Maybe I will even post pics with scientific arrows pointing to all the subtle differences

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Remember the people who originally tell us that we should replace our trainers after roughly 500 miles are the "experts" from the shoe companies. Now why would they suggest that I wonder.......

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I run because I don't have to.

Shoe companies that even market shoes based on the unique selling point they are guaranteed to disintegrate after 100k

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ive just order a second pair so will try and get some piccys vs my 4 month old pair (*yawn*)

well my second pair of mizumo wave inspire 4's has arrived... and to be honest i was quite surprised at the difference

first pair was bought around may and have done about 350-400 miles i rekon.

the pics were off my phone, the main area i noticed was how much difference there was between the depth of the heel. the old pair measurs about 13mm with the new pair being about 25mm!! but i am a heel striker.

also the balls off me feet have lost about 3-4mm of grip.

they also smell a lot nice

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Wow! quite a difference! Very useful post Beasty

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But it's all marketing apparently

Well it's good have have the photo's up so people can decide for themselves eh? I certainly wouldn't have felt there was anything wrong with my old trainers until buying some new ones, since their degredation is so progressive you wouldn't notice it... for all intents and purposes they can go on a lot further, just with reduced levels of cushioning and support!

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For the first time I'll need to buy a new pair of shoes as I've gone through the toe...all that downhill running at Davos.

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One small step for man.....

Just got myself a second pair of shoes Stayed well clear of the Nike shoes since Im not getting on with my current pair if I go on a long run, tried the New Balance 768s again just in case my feet were having a bad day but they are too short and the next size up will be way too big Shame because I love my NB shoes.
Ended up with Saucony Pro Grid Guide's, feel really comfy but all will come out with my next run. Fingers crossed they are as good as the NBs I had and produce zero blisters....unlike my Nikes.....

Just need to try and keep them clean now

O.

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"Sure you've flirted with quitting every now and then. But as long as you don't action it, Running will pretend not to notice."

nice one O, out of interest where do you buy your shoes?

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MD

Was 19'6" (May '08), now 16'0".......14'13" here I come!!!

Get them from Run and Become in Edinburgh, brilliant shop with really helpful staff and if you are a member of a club or have Scottish Athletics membership you get a further 10% off your shoes and clothing

Run and Become website

O.

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"Sure you've flirted with quitting every now and then. But as long as you don't action it, Running will pretend not to notice."

I once got over 1000 miles for a pair of shoes, and even still they didn't look physically worn. In fact I've never had a pair of shoes look visibly worn, but I do now replace after 600 or 700 miles to play it safe. Don't want to tempt fate. I've done 450 in my current pair and they still look and feel brand new. Maybe I've just been lucky or I have a strange gift

Oh, I've also never had an injury or even a niggle (touch wood). The worst I've ever got from running is aching legs once in a while

Im going to keep a note how many miles this new pair have done. My nikes are still fine and I will continue to use them but I wanted to pairs so I could have a dry pair available. They had a look at my very first pair of runners, which I use for day to day walking, and they said they should be replaced if I was still running in them as the heel has worn away at an angle making the landing potentially dangerous.

O.

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