Running in worn-out shoes is one of the most overlooked causes of running injury. The midsole foam that cushions and supports your stride degrades long before the upper looks worn — meaning your shoes can feel fine on the outside while offering almost no protection underneath.
Here's how to know when it's time to replace your running shoes, and what to watch for before your body tells you first.
The General Rule: 600–800km
Most running shoes are designed to last between 600 and 800 kilometres before the midsole cushioning degrades significantly. That translates to roughly:
- 5–6 months for a runner logging 30km per week
- 8–10 months for a runner logging 20km per week
- 12+ months for a casual runner doing 10km per week
These are guidelines, not guarantees. Heavier runners, those who run on rough terrain, and those who wear their running shoes for everyday use will see faster degradation.
Why Midsole Foam Matters More Than the Outsole
The outsole — the rubber on the bottom of your shoe — is built to be tough. It can look relatively intact long after the midsole foam has compressed and lost its ability to absorb impact.
The midsole is where the real work happens. It's the layer of EVA or proprietary foam (like HOKA's CMEVA or ASICS' FlyteFoam) that cushions your stride and supports your gait. Once it compresses, it doesn't recover — and running on a dead midsole is essentially running on a hard, flat surface.
6 Warning Signs Your Running Shoes Are Done
1. The “thumb test” fails
Press your thumb firmly into the midsole from the side. Fresh foam should feel springy and resistant. If it compresses easily and doesn't spring back, the foam is dead.
2. You feel every pebble
If the road surface feels harsher than it used to, your cushioning has degraded. This is one of the earliest signs runners notice.
3. New aches in familiar places
Shin splints, knee pain, or plantar fasciitis that appear without a change in training load are often a sign of shoe breakdown — not overtraining.
4. The heel counter has collapsed
The rigid cup at the back of the shoe that holds your heel in place should stay firm. If it's soft or folds inward easily, the shoe's structural support is gone.
5. Uneven wear on the outsole
Some wear is normal. But if the outsole is worn through to the midsole, or the wear pattern is dramatically uneven, the shoe is past its useful life.
6. You've hit 700km+
If you track your mileage (and you should), 700km is a reliable trigger to start evaluating your shoes — even if they feel fine.
👉 Related: Signs Your Running Shoes Are Worn Out: A Guide
How to Track Your Shoe Mileage
The easiest method is to log your runs on a platform like Garmin Connect, Strava, or Nike Run Club and assign shoes to each run. Most platforms will alert you when a shoe approaches a set mileage threshold.
If you run without a GPS watch, keep a simple note on your phone with the date you started the shoe and your average weekly mileage.
Does Shoe Type Affect Lifespan?
Yes — significantly.
- Max-cushion trainers (HOKA Clifton, ASICS Nimbus) tend to last toward the higher end of the range due to their larger foam volume.
- Carbon plate racing shoes often have a shorter lifespan — sometimes as little as 300–500km — because the foam compounds used for energy return degrade faster.
- Lightweight trainers and tempo shoes typically fall in the 500–700km range.
- Trail shoes vary widely depending on terrain but generally last longer on the outsole while the midsole degrades at a similar rate to road shoes.
When to Replace vs When to Rotate
One of the best ways to extend the life of your shoes — and reduce injury risk — is to rotate between two pairs. Foam needs 24–48 hours to fully decompress after a run. Alternating pairs allows each shoe to recover fully between sessions, extending the lifespan of both.
Many Durban Runner customers run in a max-cushion trainer for easy days and a lighter, more responsive shoe for tempo and race efforts. This approach protects your body and your investment.
Ready for a New Pair?
If your shoes are showing any of the signs above, don't wait for an injury to confirm it. Come into Durban Runner and let our team assess your current shoes, check your gait, and fit you into the right replacement.
Shop running shoes at Durban Runner →
Book a RunEasi gait assessment →
Written by the Durban Runner Specialist Team