Making running shoes last
A running shoe does not wear out all at once: it wears by zone, at a different rate depending on where you run. Learn to read it before you replace it.
Updated October 7, 20263 min read
The wear is not spread evenly
The first thing to accept is that a running shoe wears very unevenly. The forefoot, where you push off to leave the ground, does much more work than the heel if you land midfoot, and the opposite if you land on your heel. The outsole itself barely wears in the middle: it goes at the outer edges and along the line of the gait, where the foot rolls outwards at the end of the run.
The consequence is direct: the age of the shoe means nothing. A pair can be fine on the outside and finished on the inside, or the reverse. The only judge is the midsole, and the only time you really see it is when the shoe is damp and you take the insole out.
Two pairs beat one
The midsole -- the material that absorbs impact -- needs time to recover its shape after a run. A single pair worn every day never fully recovers: it is still deformed when the next run starts. Two pairs used in rotation give each the time to come back, and it is the cheapest way to extend their life.
If the budget does not stretch to two pairs of running shoes, the alternative is rotating the running pair with a pair of everyday shoes. It is not the same thing, but the principle holds: a midsole that never rests wears faster, and it is the resting that preserves it, not the strength of the material.
Do not wait for pain
Pain is a late signal and a badly located one. An irritated Achilles tendon can come from a finished midsole, a tight tendon, or harder ground than usual; the ankle does not say which. Waiting for pain before changing shoes is therefore waiting for a clue that does not point at the cause.
The early signs are less dramatic and more reliable. A midsole that no longer recovers its shape after a run, a foot that slides inside a shoe that is dry, an outsole polished smooth at the edges, a shoe whose weight seems to change when you pick it up: each of these says it is time to replace it, and all of them are visible without running.
The only replacement that achieves nothing is the one made out of habit, at the end of a season. A pair can last two if you rotate it and let it dry, and last one if you keep wearing it after the shape has gone.