By now, you’ve probably heard that the majority of women are wearing the wrong bra size. But, do you know you are most likely wearing the wrong sports bra size too? (Cue the double ouch while executing that perfect squat jump.)

In fact, studies find that 80 percent of women wear the wrong bra when it comes to lifestyle and active bras—and you might not even know it.

Luckily, the pros at Sweaty Betty are here to save the day—and your chest. They have spent the last 18 years not only researching sports bras and how to find out if you’re wearing the wrong size, but have become experts at creating the perfect sports bras for any size and activity. (Consider us impressed.)

“I think the most common problem that women face—and it’s ultimately why people wear the wrong size—is that they don’t know how a sports bra should actually fit before they put it on,” explains Jessica Adamson, underwear designer at Sweaty Betty. “Perhaps surprisingly to some, a well-fitted sports bra should feel noticeably tighter than a regular everyday bra.” In other words, you gotta lock ’em in, ladies.

If you’re not sure what exactly qualifies as a “tight, but supportive” fit, the team at Sweaty Betty is sharing their at-home sizing guide, so you can focus on crushing your burpees and box jumps—instead of adjusting your bra.

And even though many sports bras fall under small, medium, or large, it’s important to know your cup size going into your day of shopping, says Adamson. But she urges everyone to be wary that every brand translates a little differently, so definitely check on their website for how the sizes convert.

The Sweaty Betty At-Home Sizing Guide

Calculating underband measurement:
1. Place the measuring tape around the underbust, ensuring that it is sits flat and horizontally, and pull the end of the tape tight so that it overlaps at the front.2. Take a note of this measurement in inches, rounding up to the next full number.3. If this is an even number, add 4 inches. If this is an odd number, add 5 inches. (For example: If the underbust measures 28 inches, the underband size will be 28+4=32 inches.)

Calculating cup size:
1. Place the measuring tape around the fullest part of the breast, normally at nipple level, ensuring that it sits flat and horizontally around the body. Pull the end of the tape so that it overlaps at the front ensuring that it fits loosely, so not pressing into the breasts.2. Take a note of this measurement in inches, rounding up to the next full number.3. Sizing:If this measurement is the same as the calculated underband measurement then this will be an A cup.+1 inch more than calculated underband—B cup+2 inches more than calculated underband—C cup+3  inches more than calculated underband—D cup+4  inches more than calculated underband—E cup+5  inches more than calculated underband—F cup

Now that you’ve got your size down pat, scroll down to see the season’s cutest bras, for every activity.

Ultra Run Bra, $65

This bra can handle even the highest level of activity, no matter what cup size you wear. The convertible straps allow for extreme comfort and support whether you’re sprinting down the street or tapping it back on the bike. Plus, it extends all the way to an F cup size, which is pretty hard to find in a cute sports bra.

Upbeat Zip Padded Bra, $70

Another bra that’s perfect for medium-impact activities like boxing to circuit training, this bra has an extra special feature—a front zipper. Say goodbye to those near-shoulder-dislocation moments when taking off a sweaty sports bra!

Brahma Yoga Bra, $65

Made for low-impact activities like barre and yoga—hence the name—this bra features a wide compression-fit underband and double-duty straps that offer premium support so you can finally tackle that headstand—worry-free—and look super chic while you do it.

To find your perfect sports bra fit using the Sweaty Betty At-Home Sizing Guide, go to sweatybetty.com 

Photos: Sweaty Betty