What is the Best Underwear for Working Out?

Key Takeaways

• The best underwear for working out combines moisture-wicking stretch fabric, a breathable cotton gusset, and a cut that stays put.
• For sweaty sessions, choose nylon and spandex microfiber over all-cotton, and save cotton for low-impact days or sensitive skin.
• Match your style to your workout: a thong or bikini for leggings, a brief or hipster for high impact, and an anti-chafe short for runs and rides.
• To avoid panty lines and chafing, pick seamless or no-show pairs with flat edges in a shade close to your skin tone.
• Your underwear should fit snugly without digging in, and a sports bra at the right support level finishes your base layer.

If you've ever cut a run short because your underwear rode up, bunched, or stayed soaked, you know the right pair matters. The best underwear for working out uses moisture-wicking stretch fabric, a breathable cotton gusset, and a cut that stays put. Get those three things right and you'll stop thinking about your underwear mid-workout.

This guide is for women who train, whether that's yoga, lifting, HIIT, or long runs. We'll cover which fabrics handle sweat best, which styles suit which workouts, and how to avoid panty lines and chafing. You'll also learn how workout underwear should fit and what to wear with it up top.

What Makes Underwear Good for Working Out?

Good workout underwear pulls sweat away from your skin, stretches with you, lies flat under tight clothes, and stays in place without digging in. Everyday pairs might check one or two of those boxes. Gym underwear needs all of them, because sweat and movement expose every weak spot.

Here's what to look for when you shop for the best underwear for working out:

• Moisture-wicking fabric: Moisture wicking underwear for women moves sweat to the fabric's surface, where it can evaporate instead of sitting on your skin.
• Quick-dry performance: Quick dry underwear feels lighter between sets and after class, so you're less clammy on the way home.
• Four-way stretch: Fabric that stretches in every direction moves with squats, lunges, and deep hip openers without pulling.
• Flat or seamless edges: Edges without thick elastic or bulky stitching reduce rubbing and hide under leggings.
• A cotton gusset: Every Thirdlove pair has a cotton gusset, which keeps the most sensitive area breathable.

Is Cotton or Synthetic Fabric Better for Sweaty Workouts?

For sweaty workouts, nylon and spandex microfiber is usually better than all-cotton underwear because it wicks moisture and dries faster. Cotton absorbs sweat and holds onto it, so it can feel heavy during a hard session. That said, cotton still has a place in your drawer.

Cotton underwear is naturally soft and breathable, which makes it a comfortable pick for low-impact movement like walks, stretching, or gentle yoga. If your skin is sensitive, the Organic Cloud Cotton Brief and Organic Cloud Cotton Thong are soft organic cotton options. For heat and heavy sweat, thermoregulating fabric adds another layer of help.

Thirdlove's TempSync™ styles use 37.5® Technology, with active particles from volcanic minerals that speed sweat evaporation and help delay overheating. Here's how the three fabric types compare:

Which Underwear Style Is Best for Your Workout?

Thongs suit leggings and yoga, bikinis suit everyday training, hipsters and briefs suit high impact, and anti-chafe shorts suit running and cycling. Coverage and leg shape change how a pair behaves when you move. Match the cut to the motion you do most.

Thongs for Leggings and Yoga

A thong gives you minimal coverage and no visible lines, which is why so many women choose thong underwear for leggings. The ComfortStretch Thong is sleek and chafe-free, so it stays comfortable through flows and inversions. If you prefer natural fibers, the Organic Cloud Cotton Thong disappears under leggings too.

Panties

TempSync™ Lingerie Thong

$22

Select Size

Panties

Zero Edge™ Invisible Thong

$10 $20

Select Size

Panties

24/7® Classic High Waist Thong

$5 $20

Select Size

Bikinis for Everyday Training

A bikini is the easiest all-rounder, with a bit more coverage than a thong and a low profile. The ComfortStretch Bikini has four-way stretch, lightweight moisture-wicking fabric, and seamless construction that lies flat. Thirdlove calls it wedgie-proof and names it the best no-show underwear for working out, whether you're jogging, lifting, or doing yoga.

Panties

TempSync™ Lingerie Hipster

$24

Select Size

Panties

Zero Edge™ Invisible Hipster

$10 $22

Select Size

Panties

All Day Lace Bikini

$12 $24

Select Size

Hipsters and Briefs for High-Impact Workouts

For jumping, sprinting, and HIIT, fuller coverage keeps your underwear from shifting. Choose based on how much coverage you want:

• 24/7® Classic Brief: Full coverage that stays in place without digging in, so you avoid wedgies during high-impact sessions.
• 24/7® Classic Hipster: A mid-rise cut in lightweight signature microfiber with full back coverage that holds through planks and dance cardio.
• Organic Cloud Cotton Brief: A higher waist in organic cotton, better suited to low-impact days than all-out intervals.

Panties

24/7® Classic Brief - 3 Pack

$19 $39

Select Size

Panties

24/7® Classic Brief - 3 Pack

$19 $39

Select Size

Panties

24/7® Classic Brief - 3 Pack

$29 $39

Select Size

Anti-Chafe Shorts for Running and Cycling

If your thighs rub on runs or rides, anti-chafe underwear in a short cut creates a barrier between your skin. The TempSync™ Anti-Chafe Short pairs that coverage with thermoregulating fabric for long, warm sessions. For more length, try the Thermoregulating TempSync™ Bike Short.

How Do You Avoid Panty Lines in Leggings?

To avoid panty lines in leggings, wear seamless or no-show underwear with flat, stitch-free edges in a shade close to your skin tone. Thick elastic and seams press into fabric and show through when it stretches. Color matters too, since bright or dark underwear can show through thin or light leggings.

These choices make the biggest difference when you're shopping for underwear for leggings:

• Seamless construction: Thirdlove's seamless underwear is stitch-free and comes in thong, bikini, boyshort, and brief styles.
• No-show edges: The Zero Edge™ No-Show Thong, Hipster, and Cheeky are built to vanish under fitted clothes.
• Multipack basics: The Form Seamless Hipster comes in a 5 pack, so you have a clean pair for every training day.
• Squat test: Try your pair with your leggings in a deep squat in good light before you head out.

Want seamless workout underwear with more coverage? The Seamless Stretch Cotton Boyshort covers more of your hips and keeps a smooth line.

What Underwear Prevents Chafing During Exercise?

Underwear with flat or seamless edges, stretchy moisture-wicking fabric, and a secure fit prevents chafing best, and anti-chafe shorts help most with thigh rub. Chafing happens when damp fabric or skin rubs repeatedly in the same spot. Reduce the moisture and the friction, and you reduce the irritation.

The ComfortStretch Bikini's seamless build removes the bulky stitches that rub, while the ComfortStretch Smoothing Anti-Chafe Short covers your inner thighs. Pick a pair that doesn't bunch, since folded fabric creates new friction points. Breathable underwear for working out also helps, because drier skin is less likely to chafe.

How Should Workout Underwear Fit?

Workout underwear should fit snugly without squeezing, so it stays in place through every move and leaves no marks. Too loose and it bunches or rides up. Too tight and the edges dig in and create lines.

Run through this fit checklist when you try a new pair:

1. Waistband: It sits flat against your skin without rolling down or cutting in when you bend.
2. Leg openings: They hug your leg without gaps, and they don't leave red marks after you take them off.
3. Back coverage: The back stays where you put it through squats and lunges, with no creeping.
4. Gusset: It lies flat and centered, with no gaps or folds when you move.
5. Size: Thirdlove's workout underwear runs XS–3X, so size up or down if any point above fails.

Not sure about your size? You can chat with a fit stylist, and free exchanges within 60 days make it easy to swap a pair that doesn't feel right.

What Should You Pair With Your Workout Underwear?

Pair your workout underwear with a sports bra matched to your workout's impact level, so your whole base layer supports you. A great pair of underwear won't help much if your bra lets you bounce. All Thirdlove sports bras are made with moisture-wicking technology, so your top and bottom handle sweat the same way.

Use your usual workout to choose your support level:

• Muse (low impact): Built for yoga, walks, and other gentle movement.
• Flex (medium impact): Made for Zumba, spin, and similar classes.
• Kinetic (high impact): Designed for running, HIIT, and plyometrics, and the Kinetic Adjustable Sports Bra won the 2026 Shape Fitness Award.
• TempSync™ Sports Bra: A thermoregulating option that pairs with TempSync™ underwear for hot workouts.

Ready to Build Your Workout Underwear Drawer?

The best underwear for working out matches your workout. Choose a thong or bikini for leggings, a brief or hipster for high impact, and an anti-chafe short for runs. Keep a few moisture-wicking pairs in rotation, and add a sports bra at the right support level to finish your base layer.

Once you've picked your styles, get your sizing right across bras and underwear. Take the Fit Quiz to find your fit, then build the best workout underwear for women around the way you train.