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Read moreHow to Find the Best Sports Bra for Running Based On Your Bra Size

Have you ever wondered about the importance of wearing a sports bra when running? A study by the University of Portsmouth reveals that it's paramount that you do. According to the study, wearing ill-fitting bras that fail to restrict the side-to-side movement of breasts and offer adequate support can damage your tissues and ligaments. The researchers also confirmed that the quality of the bra affects your running style and shortens your stride.
Therefore, choosing a good sports bra for running should be a priority for any female runner, not an oversight. Now that you understand the importance of wearing a perfectly-fitting sports bra for running, let's learn how to pick the best one.
Should a Sports Bra be the Same Size as Your Regular Bra?
Most companies only provide sports bras in alpha sizing (XS-XL, ect) but at ThirdLove, we provide our high impact sports bras in regular cup-band sizing for the ultimate support. Whether you’re purchasing an alpha sized sports bra, or a regular bra-sized sports bra, you’ll need to know your exact measurements to find the perfect fit. Here’s how to find your sports bra size in a few simple steps.
How to Measure Your Cup Size
Step 1: Measure around your rib cage by placing a measuring tape beneath your breasts. You should hold the tape snug so it doesn’t fall down, but loose enough to slide two fingers underneath comfortably. If the measurement is even, add 2 inches, and if it is odd, add 3 inches. This is to account for the size difference when the elastic band is stretched or relaxed. This is your band size!
Step 2: Place the measuring tape on the fullest part of your breasts, usually near the nipple. Don't forget to hold the tape slightly loose, just like you did earlier. Note down your bust measurement.
Step 3: Find your Cup Size by subtracting your band size from your bust measurement. A difference of 0 inches is considered an AA cup, and for every inch, you want to increase 1 cup size. So 1 inch would be A cup, 2 inches would be B cup, 3 inches is C cup, and so forth. If you’re in between cup sizes, we offer half cups as well for the perfect fit!
If you would like some more help finding your perfect bra size, take our quick online Fitting Room Quiz to find your perfect size and style in just a few questions. And for additional help, always feel free to chat with and ask any of our fit stylists!
Picking the Right Level of Support
You learned how your breasts move up, down, and sideways while running, making the right level of support a high priority. Remember that the type of activity and your cup size usually determine the level of support you need. Also, remember that smaller-chested ladies might get away with medium-impact bras for even running, but those with larger busts require more support, even for less intense activities.
Let's learn more about the levels of support different bras offer and how to choose the best sports bra for running.
Low-Impact Sports Bras
Low-impact sports bras provide gentle support for walking, yoga, and weightlifting. Typically featuring removable cups, little to no padding, and thinner shoulder straps, they are generally lightweight.
Medium-Impact Sports Bras
Featuring built-in or removable cups and wider bands, medium-impact sports bras offer moderate support. These are more suitable for activities such as cross-training and hiking, although you should consider your cup size before deciding.
High-Impact Sports Bras
High-impact sports bras for women come with defined cup structures, thicker bands, adjustable straps, and padding to maximize support and encapsulation. It's recommended that medium to large-chested women wear high impact sports bras when running and for activities such as mountain biking and aerobics.