“Many injuries of the feet and ankles can be traced back to ill-fitting shoes,” says Megan Leahy, D.P.M., a podiatrist at the Illinois Bone & Joint Institute in Chicago, Illinois. But with thousands of model options—all of which change in form and functionality more frequently than T. Swift releases a hit single—how do you know if you’re wearing bad shoes? Read this before sole searching.

Blister-prone? You’re not alone. This is the most frequent complaint of marathon runners, according to a University of Cincinnati study. While blisters can pop up because of the wrong socks (or shoe-sock combo), a bad shoe that rubs you the wrong way can do it on its own. “You shouldn’t need to ‘break in’ a pair—they should feel comfortable and fit appropriately out of the box,” Bryant says.

When you’re clipped in using those stiff-soled cycling shoes, “the continual pressure in the ball of the foot can cause nerve irritation, which results in a burning feeling near your toes,” Leahy says. Ease in to the length of your spin sessions or outdoor rides and seek out a cycling shoe that has a cushioned footbed. (We’re obsessed with these slip-on cycling shoes that are a breeze to walk in, too.) Keep the strap nearest to your toes a bit looser than the others for some wiggle room, too.

These tiny bone breaks can happen to anyone, but they’re occasionally linked to minimalist sneakers. “Half of the population are heel strikers and half are forefoot strikers,” says Bryant. For those who hit on their heels, minimalists are bad shoes since they don’t offer enough cushion to absorb shock, which can lead to stress fractures, joint inflammation, and other injuries.

“The minimalist trend originated when people wanted to run like our ancestors, but we don’t run on sand or dirt as much anymore. When the ground, like the sidewalk or bike trail, doesn’t give underneath us, the body gives instead,” Leahy says. If you’re among the heel-striking population, lean toward more conventional kicks. (Related: Why Your Running Stride Is Fine As-Is)

Inflamed tendons can happen in several places in the foot, but are most common on the inside of the ankle or outer edge of the foot. The former is caused by the foot rolling inward, meaning a more structured shoe is needed, while the latter is caused by an arch that provides too much support. Ask a podiatrist how to ease back in to your workout routine safely and how to find a shoe that won’t lead to achy tendons again. (Related: Why You Need to Change Your Diet When You’re Injured—and How to Do It Right)

Should you select a neutral shoe? Or would a motion control, minimalist, or stability shoe be a better fit? The best way to tell, without visiting a sneaker fitting pro, is to take the “wet test.” “Step on a piece of paper or dry spot of concrete with a wet foot, then look at the arch area. If you can see the whole footprint mark, you probably have flat feet that tend to roll inward,” Bryant says, so a motion control shoe would work best. If there’s little proof of a print between the ball of your foot and heel, you have a high arch and would likely feel best in a neutral sneaker that absorbs shock. And if your print is somewhere in the middle, snag a stability shoe for a mix of cushioning and control.