A woman’s body changes approximately six times in her lifetime because of weight gain or loss, pregnancy or hormonal changes, says Nethero. For the proper support, get fitted once a year or anytime your body undergoes a drastic change.

Breasts can weigh anywhere from 10 ounces to 10 pounds each! Although most women today hope to be a C cup, according to a poll by Intimacy, the average cup size is a D or DD cup, says Nethero. It’s important to get fitted early and embrace your size.

One reason your size may surprise you is every time you move back a width, you must move up a cup size to maintain volume. A 36B is equal to a 32D. And don’t think of bra-cup sizes like your grades in school, Nethero warns. “An E or an F is model size,” she says. An ideal figure in America today is to be larger on top and smaller on the bottom, so even a G is proportionate.

“Think of a bra like a seesaw or a bridge,” Nethero says. If it’s low and firmly planted, it will lift in the front. If the bra starts to ride up the back, creating a ridge of tissue, or “back fat,” then the straps become too long, so you tighten them and cause shoulder strain. A proper band width should eliminate the chance of back fat and stress on your body.

There are only two times you should not wear an underwire bra: while nursing and after surgery. Underwire bras provide maximum stability and support while giving the best shape. “People are afraid of underwires because the idea sounds harsh . . . but if your bra fits properly, you should not feel the underwire,” Nethero says.

Alterations can be made to a bra if it isn’t perfectly snug off the rack. Ninety percent of your support comes from the band fitting tightly. Band-width measurements increase by increments of two, without the option of the “in betweens,” Nethero says. Your bra should feel tight at its loosest position when first purchased  so that as the bra stretches, you can tighten it. You can also make a bra last longer by opting for alterations rather than tossing it out when it gets loose.

Rashes underneath the breast tissue are a common complaint heard from women who exercise regularly. A properly fitting bra with adjustable straps should help prevent skin-on-skin contact, which leads to sweat traps and irritation. A good test to ensure you have the right fit: Jump in place when in the dressing room.