It’s a question we get all the time:
“How do I know when my shoes are worn out?”
There are a lot of answers to this oft asked question. Unfortunately most people use pain as their barometer for shoe replacement. An aching shin, hip, or old knee injury starts to act up and that gives the indication that the shoe is worn out. Which isn’t a terrible way to do things, but you’re playing with fire a little bit. We’re not into rehab, we’re into PRE-hab!
The general rule of thumb is that your shoes should be retired every 300-500 miles. This is a broad range however, and is dependent upon multiple factors: the type of shoe, the body type and footstrike of the wearer, what other activities you’re partaking in in said shoe, and the surface(s) run upon. So we will touch on some of these:
Shoe type: People love their lightweight shoes. Keep in mind however that trimming down on the shoe’s weight also sacrifices some durability. If you’re a big fan of lightweight trainers and minimal shoes, generally speaking these shoes won’t get quite the same life as a more traditional trainer. This is even more the case if you are a larger framed runner who is naturally harder on shoes.
Runner’s Body Type/Footstrike: The more weight that is coming down on the shoe, the more life that gets taken out of the shoe. This is obvious, given that 3-5+ times your body weight impacts your shoe with every stride, so a 250 lb. runner will naturally go through shoes a bit faster than an 80 lb. middle schooler. However, a heavier runner with an extremely efficient footstrike could possibly be easier on a shoe than a slightly lighter runner who really pounds the ground.
Running Surface: The harder the surface, the more of a beating your shoes (and body) take. If you’re a fan of concrete, expect to replace your shoes more often than you would if you take the trails to the most. It’s a good idea to mix it up anyway, given pavement’s propensity toward beating up the legs in addition to the shoes.
Other activities: People often ask if it’s “bad” to use their running shoes for other activities. And no, it’s not “bad” for you or the shoe, it simply takes more life out of a shoe to be running, lifting, cross training and walking around in your trainers than simply reserving them for runs. So if you keep your running shoes solely for running, you’ll get more miles from them.
So given all these factors, this brings up back to our initial question. How do you know when your shoes are done-zo without waiting for something to hurt? Keeping all of these other things in mind, it never hurts to keep at least vague track of your miles. Keeping track of how long you’ve had them is much less effective because really, it’s all about how much they’ve been used. If you just can’t be bothered to keep track of mileage, then check every so often how soft and “mushy” feeling your shoes are getting. When they’re overly-flexible and squishy compared to what they used to be, and there are horizontal creases in the foam from compressing (especially in the “posting” if you’re in a stability shoe), it may be time to replace them. Don’t wait for the tread to be gone as the cushion was gone well before that.
So there are a myriad of things to keep in mind to gauge the life of your shoe, and while the 300-500 mile rule is a good one, there can be a great deal of variation from runner to runner. So watch how much use you’re putting them to, and give them a lookover every so often, and it’s likely you’ll figure it out for yourself.