It might seem like a ploy to get you to buy new kicks more often, but the materials in athletic shoes really do have a shelf life—they break down with use and over time. “The soft, bouncy materials that make up a shoe are designed to provide cushioning and support,” says Jordan D. Metzl, M.D., a sports medicine physician and author of Running Strong. “But the more you wear your shoes the more those materials pack down and lose that springy-ness.” Which is why most companies recommend trading in running and walking shoes after anywhere from 300 to 500 miles.
That certainly doesn’t mean you need to buy the priciest sneakers on the shelf. In fact, a survey completed by a Danish company reveals expensive running shoes are no better—and in some instances, according to consumer reviews, worse—than cheaper options. Still, the signs of wear and tear remain the same. Here’s how to know when it’s time to buy a new pair of athletic shoes.
1. YOUR SHOES ARE LOOKING WORN
Look for general wear and tear, says Metzl. “If the treads are gone, they will no longer provide grip or traction and could lead to slips and ankle twists.”
2. YOUR KNEES FEEL ACHY
Worn out cushioning material can lead to achy knees and hips. “When your shoes reach the point where the midsoles no longer compress, it’s a sign they are no longer cushioning your movement, which puts more pressure on your body, especially on the joints,” says Metzl.
3. YOUR KICKS HAVE TOO MUCH GIVE
If they still feel loose—no matter how tight you lace ‘em, it’s time to slip on a new pair. “Shoes stretch out over time, and if you continue to use them you may notice friction from rubbing in certain areas, which can lead to blisters,” says Metzl.
4. YOU SET AN INTENTION TO MOVE MORE!
An investment in your attire might be just the push you need to stay motivated beyond January. “I love the way a new pair of shoes feels,” says Metzl. “That extra spring always encourages me to take more steps!”