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When it Comes to Your Sports Bra, "Size Matters". Read our detailed guide to learn how to measure and identify the best bra size for your next run.
Updated: July 26, 2023
Did you know that eight out of ten women are wearing the wrong size sports bra? That means that most women are not having the positive and comfortable running experience that they deserve. Proper sizing is arguably the most important factor in a sports bra's overall comfort. A bra that is too big will not provide adequate support, and a bra that is too small can restrict movement and breathing. We would like to change women's sports bra experiences by ensuring that they are in the right size for their individual bodies. Follow these simple steps to learn how to find a sports bra that fits you perfectly.
Step One: Find Your Band Size
So how do you find your size? The first step is to take a few measurements, which you can either do yourself or have a trusted companion do for you. You’ll need a soft tape measure in order to find your band size and cup size.
We have found that the best way to find your band size is actually to measure above the bust, just below the armpits. This may seem a bit counterintuitive since the band of a bra goes in a completely different place, but it turns out that measuring below the bust can provide incorrect sizing for women with certain shapes of ribcages. The measurement that you take here, across the top of the bust, is your band size.
Step Two: Find Your Cup Size
To find your cup size, start by measuring around the fullest part of the bust. Make sure that the measuring tape is kept level and is not too tight. Round this measurement up to the closest inch and subtract the band size you measured in the first step to find the difference. Use this number to find your cup size by consulting the chart below:
| Difference (bust - band) | Cup Size |
|---|---|
| 1" | A |
| 2" | B |
| 3" | C |
| 4" | D |
| 5" | DD |
| 5.5" | E |
| 6" | F |
Now that you know your measurements, you can use brand sizing charts to find your correct size bra. Keep in mind that different brands may size their bras a bit differently, so just because you're a certain size in one brand, that doesn't necessarily mean you're that same size in another brand. Be sure to check each brand's sizing chart just to be sure.
Step Three: Find Your Support Level
The level of support you need depends on the type of activity you are doing and your cup size. Different activities and different body types require different bras. Just like you wouldn’t wear that lacy little number on a backpacking trip, you might not want to wear your yoga bra while going for a run. Different exercises create varying levels of impact and movement of the breasts.
Smaller chested runners may find that wearing a low-medium impact level sports bra offers adequate support for running, whereas those with larger bust sizes need more structured support that high impact sports bras provide. The following are the three different support levels that sports bras are categorized into:
- High-impact support bras limit excess movement and provide maximum support and protection. For activities that include a great amount of motion like running, larger chested runners find that high-impact sports bras provide optimal, bounce-free protection and a secure fit. Some features of a high-impact bra include a thicker band and padding, which could be in the form of removable pads or built-in cups that offer a natural silhouette by keeping each breast separate for targeted support. High impact bras may also feature adjustable straps to dial in the fit and a hook/eye fastening for easy on/off wear, making it ideal for larger cup sizes.
- Medium-impact support is suitable for most runners who don't want a highly compressive fit. They offer a moderate level of support and modest coverage. Average to smaller chested runners find that medium-impact sports bras provide sufficient support for running. Activities such as hiking or cross-training on the elliptical are also suitable in medium impact sports bras. These bras may feature removable padding for coverage, wider secure straps, thicker under band for support, and a compressive design that presses the breasts against the chest to minimize movement. Racerback is one of the popular design features of medium impact sports bras, which offer more mobility and easy wear and removal for those with smaller bust sizes.
- Low-impact support offers minimal compression and is ideal for smaller chested runners, those seeking a comfortable option, or for loungewear. Low-impact sports bras also offer versatility in providing support for activities with a low degree of bounce like yoga, pilates, and weightlifting. Low impact bras are generally lightweight, feature thinner shoulder straps, no padding or removable cups, and supply light, gentle compression.
In summary, the amount of support you need is dependent on the activity you are engaged in and your cup size. If you are a smaller cup size (think A/B cup), you will find low-medium impact sports bras are efficient for running. But if you have a C-cup bust or larger, you'll want more high-impact specific features to minimize bounce.
Read more about the different style features of sports bras designed to add comfort and support in our article on How to Choose the Perfect Sports Bra for you.
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