Sports Bra Support
Different bras offer different levels of support. The type you need will depend on your cup size and the type of exercise you do.
1. Low-impact sports bras, used for stretching or walking, are often cut like a crop-top and are, on the whole, made from thinner material.
2. Medium-impact sports bras are a mix between the two, these can sometimes be used for running, but are often not suited to larger-breasted women.
3. High-impact bras (for running) generally use less stretchy material, include supportive seams and overlays and are sometimes even underwired.
Running causes a large amount of breast movement compared with many other sports. Whilst the level of support required does vary according to bra size, whatever size you are it’s often recommend that you opt for maximum support.
For the best performance and comfort, it’s important to match sports bra support with the type of activity you’re doing. Sports bras are designed to provide three levels of support: low, medium and high support for use in low-, medium- and high-impact
Low |
Medium |
High |
walking |
moderate hiking |
running |
|
skiing |
aerobics |
strength training |
road cycling |
mountain biking |
Shop sports bras
If you participate in many different activities, it's smart to equip yourself with several different styles of sports bras—ones with more support for high-impact activities and some less constrictive ones for low-impact activities.
Sports Bra Construction

Encapsulation sports bras: These bras use individual cups to surround and support each breast separately. There is no compression in these bras (most everyday bras are encapsulation bras) making them generally best for low-impact activities. Encapsulation bras provide a more natural shape than compression bras.
Compression sports bras: These bras typically pull over your head and compress the breasts against the chest wall to restrict movement. They do not have cups built into the design. Compression sports bras tend to work best for low- to medium-impact activities.
Compression/encapsulation sports bras: Many sports bras combine the above methods into a supportive and comfortable style. These bras offer more support than compression or encapsulation alone, making them generally best for high-impact activities.
Sports Bra Features
Band: The primary source of support comes from the band, which forms the foundation of a sports bra. The band should be snug around your rib cage, but not too tight. If you can fit two fingers between your body and the band (but not more) that’s the
Shoulder straps should feel secure and provide minimal stretch to reduce up-and-down movement. As with the band, you should be able to fit two fingers between your shoulders and the strap (but not more). Wide straps better disperse the weight and offer greater comfort than narrow ones. Straps should not slip off or dig into your shoulders during high-impact activities.
Adjustable straps offer the most customizable fit and are often found on encapsulation style sports bras.
Back closure: While most sports bras are pulled on over your head, some have a back closure with hooks. In addition to being easier to get on and off, this type of sports bra allows you to further adjust the fit. When fitting a new sports bra, use the furthest hook. That way, when the bra inevitably stretches out, you can use the closer hook.
Underwire:
move moisture away from your skin and keep you comfortable. The more supportive a sports bra is, the less effective it will be at wicking away moisture because of its sturdier fabric and construction.
Sports Bra Strap Type

Tank top: This strap style is most similar to an everyday bra. The straps are often adjustable so you can fine-tune the fit. Bras with tank top straps often have a back closure, which offers additional adjustment. Some tank top bras are designed to allow the straps to be crisscrossed for versatility.
Racerback: Sports bras with a racerback have shoulder straps that come together between your shoulder blades to
Regardless of the strap type you choose, keep in mind that thin straps generally provide less support than wider straps, but thin straps are easier to conceal.
Find Your Sports Bra Size
Sports bra fitting is not an exact science, but this fit guide can help you find your basic size. Since each body is different in its proportions, you may need additional fine-tuning using adjustable straps and back closures, or trying out different styles and brands until you find the right one for your body.Step 1: Rib cage measurement.
Step 2: Band size. Using the measurement guidelines below, find your corresponding band size based on your rib cage measurement.
RIB CAGE |
BAND SIZE |
---|---|
25" - 27" |
30 |
27" - 29" |
32 |
29" - 31" |
34 |
31" - 33" |
36 |
33" - 35" |
38 |
35" - 37" |
40 |
37" - 39" |
42 |
39" - 41" |
44 |
Step 3: Bust size. Measure around the fullest part of the breast. Be sure the tape stays straight across your back. Round up to the nearest inch.
Step 4: Cup size. Subtract your rib cage measurement (step 1) from your bust measurement (step 3). The difference in inches is your suggested cup size. If you’re between sizes, round up.
BUST SIZE MINUS RIB CAGE SIZE |
YOUR CUP SIZE |
3” |
AA |
4” |
A |
5” |
B |
6” |
C |
7” |
D |
8” |
DD |
9” |
E |
10” |
F |
Measurement guidelines provided by Brooks.
Perfecting Sports Bra Fit
Now that you’ve found your size, try on the sports bra and test the fit. It should fit slightly tighter than a regular bra, but you should be able to breathe deeply and comfortably. Check the following factors:
Chafing:
Straps: You should be able to fit two fingers between the straps and your shoulders. It’s vital that the straps are secure and comfortable. If they’re too tight, they will dig in. If they’re too loose, they will not provide the correct amount of support and will move around or slip off your shoulders.
Band: Raise your hands over your head. If the band rides up, it may be too big. Try adjusting the straps or back closure. If that doesn’t work, try a smaller band size.
Cup: Your breasts should be centered and fully contained in the cups. Scoop them in and center them. Wrinkles or puckers in the fabric indicate the cup is too big. If breast tissue is pressed outside of the bra, that means the cup is too small, or that the style of bra is the wrong cut for your breast type.
Support: Test the bra's support by jumping or running in place. Your breasts should feel secure and supported. If there’s too much movement up and down or side to side, keep looking for a better-fitting bra.