The guideline of 300 to 500 miles per pair is a good generality, but Michael Aish, co-owner of the Boulder Running Company Denver Tech Center, is more concerned with how hard you wear the shoes. “If you hit the ground with a clomp and run mostly on concrete, your shoes will have a much shorter shelf-life than if you barely hear your landing and you spend a bunch of time on the treadmill,” says Aish.
Read our list of the 100 Best Running Shoes, Ever to see what kind of shoe works for your foot type.
If the elastic is so worn that the sock bunches up, you risk getting blisters. Extra-thin fabric on key pressure areas—under the ball of your foot, say—means you’re missing out on cushioning. “Fit is key with socks,” says Aish. “If your heel isn’t fully covered because the fabric is stretched out, you’re asking for trouble. Get rid of them.” (Search: Best running socks)
Learn the 5 Warning Signs Your Feet may be sabotaging your workouts.
High-impact exercise accelerates the stretching of all the components of the bra that provide support. “A good general rule is that a bra lives for no more than a year if you wear it three to four times a week,” says LaJean Lawson, Ph.D., an exercise scientist and expert in sports bra design. D cups may need to be replaced earlier. See the Best New Sports Bras for our picks that cover all cup sizes.
Related Video: Running Shoe Size and Fit
You might need to toss your bottoms if the elastic in the underwear liner is slack; if the words on the care label are so faded you can’t read them; if you have to use the string in the waistband to keep them up—or if the string is MIA.
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