If you're an athlete whose sport involves plenty of running, whether you're involved in track and field, running marathons, or triathlons, it would be a good idea to have several pairs of running shoes that you alternate every day. If you have 2 pairs, and alternate them every day during their training, the material in their heels will be able to rest during their off days. This makes them last slightly longer than if they were constantly used every day, allowing both pairs to last up to 7 or possibly even 8 months. If you alternate three pairs of shoes, then they might collectively last 10 - 12 months, instead of only 9.
Knowing these figures and probable lifelines would be able to give you a good idea when to buy new shoes, so you don't panic when your current pair suddenly implodes during training.
You can actually see the change in the material if you had a photograph of your running shoes when they were brand new. If the shoes are particularly worn, the heel areas would be noticeably shorter than when they were brand new. This is because of the constant trauma they receive from the heel strikes during running. Eventually, that material would be completely worn away to nothing.
WHAT IF YOU'RE NOT AN ATHLETE?
Running shoes typically last for around 300 kilometers. Sometimes a bit less, sometimes much more, depending on the overall quality. But, unlike a car, you can't really tell how much distance your shoes have logged unless you're a compulsive note taker. An easier way to tell if your shoes have bitten the dust and need to be buried and replaced is by the feel of the material in the heel. If you can noticeably feel the material underneath the heel padding (the area closest to your foot), then it's time to get a new pair, unless you'd rather risk possible injury.
It's a good idea to actually test your shoes from time to time like this if you feel that they're already very old because you might not feel the difference in material over time, seeing as how running, and even jogging, are much lower impact than running or sprinting.
I apologize for not giving more specific lifespans of running shoes when they're only used for casual walking. Individuals mostly walk infrequently during the day, so the shoes typically don't get that much wear. They can last for years and years if used infrequently.
Got any thoughts or questions on the life span of your own pair of running shoes? Share your thoughts by leaving a comment below!