By Kimie Bunyasaranand and Flash Santoro, Sole Sports
An almost daily inquiry at a specialty running shoe store is some form of, “How long will these shoes last?” It’s a good question, and it depends on a handful of factors—your height and weight, what terrain you’re running on, if you’re running on hills or flat surfaces, your speed, etc.
Runners typically run at a cadence of 160 to 180 foot strikes per minute, with three to five times their body weight being applied at normal paces and as much as eight times the body weight at quicker paces and down hills. As a shoe nears the end of its lifecycle, the foam becomes downtrodden and carved out in the areas of greatest impact—the lateral heel and the ball of the foot, particularly the first metatarsal. Over time, running shoes will show signs of a lack of springiness, similar to a mattress. The body weight will crush down on the foam with little return, and the shoes will begin to perform differently than they were designed—and not in a good way.
Not sure if it’s time yet? Here are a few surefire signs that you need to replace your shoes.
1. You’ve run anywhere between 300 to 500 miles in them. And that’s just running in them. Using the same shoes for other activities (going to the grocery store, lifting weights at the gym, etc.), will add additional wear on the shoes. For the average user running 15 to 20 miles per week, it amounts to roughly five to seven months.
2. You start noticing seemingly random, inexplicable pain. When the cushioning of your shoe has worn down, it provides less shock absorption and can lead to wear and tear on the joints, tendons and fascia. Sometimes knee pain, ankle pain, shin pain or even plantar fasciitis are the result of shoes that are worn down.
A good test is to bring your old shoes into a specialty running store and try on the old one on one foot and a brand new shoe on the other foot and compare the cushioning and shock absorption. Usually just standing up in the shoes, you’ll feel a difference right away.
3. Noticeable wear on the exterior of the shoe. If there are holes in the upper or the bottom tread has worn as low as the foam that used to be above it, it probably means the shoes should have been replaced a lot earlier. Also, if you can push the foam in the forefoot down easily with little resistance, it’s likely that the shoes are spent.
To sum it all up, the shoes are “done” when the resiliency in the cushioning is kaput. One way to extend the lifespan of running shoes is to alternate between pairs. It can take up to 72 hours for the foam to re-expand after use, so it helps to give them a breather before hitting the pavement again. You can use two of the exact same model, or change it up! Maybe go for a higher cushioned pair for longer runs and lighter shoes for tempo runs.
A good pair of shoes is a lot cheaper than physical therapy and certainly worth sparing yourself from the pain, anguish and stress that comes when you can’t do your sport the way you want to. If you’re not sure, visit your local running specialty store and they may be able to help you determine if you need new shoes.