The Ultimate Guide to Sports Bras

Have you ever felt lost walking into a sports store looking for a sports bra? Different styles, levels of support and sizing can be confusing. So here is your definitive guide.

Why do sports bras matter?

If you ever felt breast pain or discomfort during running, your sports bra could be the culprit. Up to 72% of women experience breast pain during exercise, often preventing them from remaining in sport.

Sports bras have also been shown to impact performance in athletes, lack of support can cause our bodies to compensate by shortening our stride (by up to 4cm) or we might feel more fatigue in our upper bodies.

Interestingly, too much support is also not good - it can cause extra strain on our spine or tight fitting bras can cause difficulty breathing.

What support level do I need?

Typically, sports bras come in Low, Medium or High Impact support.

Low support bras are great for lounging at home or maybe light movement like yoga or pilates (though some women with bigger busts might prefer a bit more support). They typically provide the least coverage, they look great but they’re not built for your next run.

Medium support bras are good for walking, hiking, gym, cycling, etc. They typically have more coverage and materials that keep shape a bit better. If you’re A-C cup, you might find this level of support enough for running too. But they’re not usually designed for high impact activities.

High Impact support bras are designed for running, HIIT, tennis, horse riding, anything with a lot of movement. They have the highest level of coverage as our breasts do move in all directions (vertically, sideways and in-and-out), usually have wider underband and straps. The materials often feel more compressive and feel sturdier. They aren’t designed to be worn all day, though a comfortable sports bra should be ok to wear for hours.

How does sports bra sizing work?

If a sports bra has ever felt too tight around your chest, but the next size up was too loose - that's not you. That's the sizing.

Typically sports bras come in either alpha sizing (S, M, L, etc.) or cup and band sizing (e.g. 34DD). You might also find a mix (e.g. S A-C, S D-DD).

Alpha sizing tends to use 32B as the base, so it’s often not the best fit for women above D cup.

Low and Medium support sports bras might be easier to find because they tend to have stretchier materials. For high support, you’ll find a much better fit with brands that offer band and cup sizing (or a mix).

If you’re not sure what your size is, check out our sizing guide and do the Fitting Quiz via our chatbot.

What about materials?

Materials are (usually) picked intentionally depending on the usage - race, training, recovery, or a reliable all-rounder. You might be used to looking for lighter materials for a race top or merino wools for your hiking or skiing holidays. But what about sports bras?

Sports bras sit on your body and material choice can make a difference. Rather than looking at the material composition (realistically, it’ll be some poly blend), I suggest looking out for:

• How does the material feel against the skin? Is it comfortable?
• How much stretch and give is there? If the material moves a lot, it’s probably not the most supportive.
• How thick is the material? Would it be heavy when wet? If padding is stitched in, does it feel light and porous?

This can take some trial and error, and that's normal. You can start by looking at your existing bras and sportswear and checking the fit.