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All of the latest sports bra tech advancements mean nothing for you if you aren’t buying a bra that fits right. It’s suggested that as many as 70 to 100 percent of women are wearing the wrong bra size, according to research by Jenny Burbage, PhD, a sports biomechanist at the University of Portsmouth. Don’t be a statistic. Keep these seven expert-vetted guidelines in mind next time you’re shopping.
1. Know your bra size!
Get fitted at a specialty bra store or even a department store to figure out your correct breast size; then, when you go into a sports store, you’re better equipped to try on the right size from the get-go and more accurately convert the sizing.
2. Choose a high-impact design.
Running is a high-impact sport. As cute and fun as lightweight, strappy designs may look, they won’t provide the support you need if you’re larger than an A or B cup.
3 Check the cups.
If your breast is spilling over the top or out the sides, it’s too small; if the front of the cup shows wrinkling, it’s too large. With encapsulation bras, the center panel should be laying as close to your chest as possible, if not actually touching.
4. The wider the straps, the better.
“If you double the width of the strap, you can almost cut the pressure per square inch in half,” says Lawson. Either way, avoid straps that lay too close to the neck (especially with racerbacks), because they can irritate the muscles around your neck.
5. Do star jumps in front of the mirror.
Ideally, you should mimic the activity a sports bra is for when trying one on; “star jumps have been shown to be a high breast movement-inducing exercise, so they’re good test to see if the bra is restricting movement well enough,” says Horler.
6. Check for seams and stitching.
Design elements like this may seem unimportant, but if your arms is rubbing against something at any point, that’s really going to show up after about six miles, says Lawson—hello, chafing.
7. Check the bottom band.
See if you can fit two fingers between your body and the band—if you can’t, it’s too tight and will restrict your breathing; you can fit more, it’s too loose and won’t be supportive enough.