All running shoes wear out eventually and once they do, they lose their effectiveness. Running in excessively worn shoes can increase your risk of repetitive injuries in the feet, legs and pelvis. There are a number of things that can help you decide if you need to replace your size 12 trainers.
According to experts at Runnersworld, you should change your running shoes after 450 to 550 miles. But if you don’t keep a log of your mileage, look out for some obvious signs of wear. If the outer sole has worn through to the midsole or if the midsole feels too soft and collapses easily under pressure, your shoes are definitely past their peak. Another test is to place your trainers on a flat surface. If they no longer stand up straight, they probably need replacing.
The frequency with which you need to change your shoes will also depend on how you run. For example, running on the road all the time will wear your shoes out quicker than running off-road. If you over-pronate and run daily, you’re likely to wear your shoes out faster than a lighter, neutral runner who runs every other day.