The Best Underwear for Working Out That a Personal Trainer Recommends

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When you gear up for a workout, you check all the essentials off your list: headphones, sneakers, water bottle, and a killer playlist. As for underwear? You probably just throw something on without a second thought. However, that second thought can make a huge difference when it comes to your health, not to mention the quality of your workout. 

Your undergarments can play an important part in your health and hygiene when you work out, but no one ever really talks about them. In fact, there’s a burgeoning industry of high-performance underwear breaking out from under the radar that’s been specially engineered for high-intensity activity, such as working out. From space-age fabrics that stay light and airy to specialized fits that ensure comfort and allow for free flexibility. But where to begin? With so many new styles popping up both on the racks and online, where do you start? We went to the experts to find out everything you need to know about choosing the best undies for working out. 

What To Look For in Underwear for Working Out

The Right Material

First and foremost, when you exercise, go for a breathable pair of underwear made of absorbent material like cotton, since your body will produce a lot of moisture while you move, recommends Suzie Welsh, RN, fertility nurse and founder of Binto women’s vitamins. To help avoid buildup of moisture or discharge, you can try moisture-wicking underwear made from polyester, nylon, or spandex. Ideally, you’ll want to make sure they’re not manufactured with additional chemicals, Welsh notes. “Since your vagina is the most absorbent part of the body, it's critical to choose underwear that's free of chemicals.”

The Right Construction

Despite having quite different silhouettes, one thing each of the following styles has in common is a certain nip, tuck, seam or gusset that lets your body move friction-free while staying in place (AKA not riding up or down). Additionally, things to avoid include elastic in the groin (think G-strings) or abrasive lace in all the wrong places, which can cause irritation, rashes, itching, and discomfort, particularly with more intense activity

The Need for Underwear at All

Prefer to go commando? It’s up to you. “I feel better wearing undies, but it’s a personal choice,” Welsh says. “Just make sure you wash your underwear between each wear to prevent bacteria build-up and irritation that will lead to uncomfortable yeast infections.” If you choose to work out sans panties, just make sure your leggings have a gusset—aka the diamond-shaped area in the crotch of your workout pants, Alyssa Dweck, MS, MD, FACOG, a New York City-based gynecologist notes. "The purpose of the gusset is to eliminate a central seam, which can irritate the vagina.”

Meet the Expert

  • Suzie Welsh, RN is a nurse, educator, women’s health advocate, and the CEO and founder of Binto, a telehealth and subscription box company that focuses on female reproductive health.
  • Alyssa Dweck, MS, MD, FACOG, is a practicing gynecologist at the CareMount Medical in Westchester County, New York. She is proficient in minimally invasive surgery including robotic surgery. Dweck is also an assistant clinical professor in the Department of Obstetrics, Gynecology, and Reproductive Science at the Mount Sinai School of Medicine and a consultant at Massachusetts General Hospital, Vincents Memorial Ob/Gyn Service.

Bottom line (pun intended): “No matter if we’re going to the office or the gym, we want our underwear to feel comfy, fit well, and allow for aeration—and we surely don’t want to give up style and feeling [great] to find this,” says Dweck. As difficult as that might sound, it’s more than possible in today’s retail landscape. 

Below, find six options that successfully check all these boxes:

Patagonia Women’s Barely There Thong

Patagonia underwear


What We Like
  • Made from recycled material

  • Super comfortable

  • Dries quickly

What We Don't Like
  • Low rise design possibly unappealing to some

Made of a nylon-spandex blend with moisture-wicking and odor control properties, this seamless thong underwear dries quickly and stays put. 

Size: XS to XL | Material: 63% Recycled Nylon, Spandex | Color: Rosewater, Black

Okko Signature Brief



What We Like
  • Waistband-free

  • Silky smooth

  • Lightweight

What We Don't Like
  • Runs one size small

  • Rides up body

These silky, seamless briefs provide a comfortable fit that won’t ride up or roll down as you move. They have a dark-colored gusset to disguise any possible period stains, and are available in a variety of skin tones. 

Price at time of publish: $16

Size: XS to XXXL | Material: 73% Nylon, 27% Elastane | Color: Onyx, Blush, Creme, Honey, Rich

Yellow Willow Yogini-Bikini

Yellow Willow Yogini-Bikini

Yellow Willow

What We Like
  • Moisture-wicking

  • Seamlessly moves with body

  • Stays put

What We Don't Like
  • Could use more color options

Invisible under yoga pants, these briefs are silky-smooth on your skin. They’re made from a quick-dry, moisture-absorbent material that won’t slide around during your workout.

Size: XS to XXL | Material: Nylon, Spandex | Color: Nude, Black

Icebreaker Siren Thong

Siren underwear



What We Like
  • Wool material regulates body temperature

  • Durable

  • Strategically placed side seams optimize comfort

What We Don't Like
  • A tad pricey

These comfy bikini-style undies are made with a merino wool blend, which some studies suggest may be naturally antimicrobial, and a touch of Lycra. In other words, they won’t start to smell, no matter how many miles you rack up.

Price at time of publish: $30 for size medium (Loden)

Size: S to XL | Material: 83% Merino Wool, 12% Nylon, 5% Lycrae | Color: Black, Fawn Heather

Pure 5.5 Women’s Brief

Pure 5.5 Women’s Brief


What We Like
  • pH balancing

  • Non-irritating, very delicate feel

  • Super stretchy

What We Don't Like
  • Runs one size small

  • Limited size range

Prefer your underwear drawer to be colorful? Opt for these stretchy and elastic pH-balancing briefs that keep your lady parts fresh, dry, and healthy.

Size: M to XL | Material: 100% Cotton | Color: Various

  • Which underwear is best for the gym?

    Aside from choosing a fabric that provides aeration, you should be looking for a style with a comfortable fit, smooth construction that won’t chafe or cause irritation in your more sensitive areas, and that looks great so you can feel great in them.

  • What underwear do you wear under gym leggings?

    Since the tight fit of leggings leaves very little to the imagination, you’ll want to choose a style that meets your needs for flexibility and breathability without causing the dreaded VPL. Go for styles without seams or trim that could show up as lumps and bumps and even cause chafing. 

  • Which fabric is best for working out in?

    As Welsh said above your first priority is breathability, and that’s where today’s crop of workout undies really shines. While lightweight cotton is probably the most common go-to fabric, there are a wide variety of synthetic options like nylon, polyester and spandex, designed to constantly wick away moisture while providing a snug, sleek fit. 

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Nicole W. A question for women’s health: chemicals in feminine hygiene products and personal lubricants. Environ Health Perspect. 2014;122(3):A70-A75.

  2. (Pdf) An investigation into the possible antibacterial properties of wool fibers. ResearchGate.

  3. Everything you need to know about maintaining your vaginal ph balance. Healthline.

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