Woman in sports bra

If you’re working out at home or heading out for a run somewhere private, it may be tempting to skip the struggle of putting on a sports bra. But the compressive garment isn’t just designed to make your chest look a certain way, it was invented in order to protect your breast health during exercise that causes your breasts to bounce. It may sound funny, but skipping a sports bra too often can have negative consequences for breast health.

"A huge number of women are experiencing some breast injury from tissue moving up and down or in and out during exercise," Susan Nethero, founder of the bra company Intimacy, told Shape magazine.

That’s because your breasts are connected to your chest by thin tissue called the Cooper’s Ligaments, and a repetitive up-and-down motion, whether it’s from running, skipping rope, or doing a dynamic movement like jumping jacks, can eventually cause pain and sagging in that tissue (via Livestrong). Unfortunately, breast size is linked directly to discomfort levels: Women with larger breasts are more likely to experience breast pain when exercising.

What should you look for in a sports bra?

happy woman in sports bra

The level of compression — how tight the bra is in order to keep your breasts from bouncing — depends on the activity you’re doing. Running will require a more high-impact bra, while slow, gentle movement like yoga means a lower-impact bra can be used. When trying on a sports bra, don’t just stand in the fitting room: Give it a jump test to see how well it controls bounce. And good news: A more supportive bra can actually improve your running posture (via Human Movement Science).

If you do have larger breasts, Shape recommends an encapsulation-style sports bra that has separate cups for more control and a more comfortable fit. But even those with smaller breasts should be seeking support: Regardless of breast size, the connective tissue can still be damaged by high-impact exercise. You may be able to wear a lower impact, less compressive bra, but some level of support is critical. Because a good sports bra can be the difference between a pain-free workout and a frustrating one, it’s important to pick bras that feel comfortable as well as supportive. Don’t be afraid to splurge on a sports bra that fits well.