Best underwear for running and strength training

13 best underwear for runners and strength trainers

Posted by for Strength

What you wear can massively impact how you perform – but it’s not necessarily the external kit that matters as much as the under armour you’ve got on. Whether you’re strength training, running or doing yoga, here are the best pieces of underwear for working out in.

Most people have a pair of leggings they swear by or a sports bra that they can’t live without, but not enough of us think twice about the underwear we work out in. Choosing the right underwear is not only crucial to our comfort while exercising but it could also prevent you from developing thrush.

“Heat and moisture can get trapped down there if you work out for a long period of time or don’t change your clothes after working out – creating a perfect environment for yeast infections to grow and thrive,” explains Dr Sarah Welsh, gynaecology doctor and co-founder of the sexual wellness brand, HANX. People who exercise, she adds, are more likely to suffer from vaginal thrush.

Choosing the correct underwear is a key part of preventing yeast infections. The other thing you can do to reduce the chances of thrush developing is changing out of sweaty clothes as soon as possible and shower after exercising, Dr Welsh explains. “But don’t douche,” she clarifies. “You might feel inclined to ‘wash out the vagina’ after exercise but this can flush away the good bacteria, such as lactobacilli, which help maintain a healthy pH and healthy vagina. Douching only makes infections like thrush worse.”

Fabric is the most important thing to consider when you are choosing underwear to workout in. Dr Welsh suggests avoiding materials like nylon that trap heat and moisture and opting for non-absorbent materials like cotton or a breathable synthetic material like some types of polyester. “Make sure the material allows you to move freely,” Dr Welsh adds. “If it’s restrictive, this may cause soreness and friction. Basically, anything that is breathable, lightweight and stretchy is a go.”

With that, here’s our guide to the best underwear to workout in. Whatever kind of exercise you’re doing – walking, running, weight lifting or all of the above - there’s a pair of knickers for that exact purpose.

Best underwear for everyday exercise

Daily walks have become part of many people’s routines since lockdown began and although it’s a fairly low-impact cardio, you’re still breaking a bit of a sweat. Comfort is always key, whatever the length of your outing.

Opt for a cotton brief or thong made from a soft material that feels comfortable on the skin and won’t rub against your bikini line. 

  • Stripe and Stare – Black Knicker

    Stripe and Star knickers
    Sturdy enough to withstand constant washing post-walk, Stripe and Star's pants are the perfeect every-day pair

    Stripe and Stare’s mid-rise knickers are made from Tencel, an eco-friendly fabric that is incredibly soft, which means these knickers are particularly comfortable. They come in a range of colours and patterns. Oh, and they’re known for their longevity –so you don’t need to worry about them deteriorating after constantly going through the wash if you’re pretty strict about sticking to your daily walk.

    Price: £15

  • Reformation – Karen Thong

    Reformation pants
    Made with Tencel, these mid-rise pants are ultra-sustainable and comfy.

    Also designed with Tencel, this Reformation pair are the perfect pants if you’re looking for that same comfortable fabric and with a mid-rise fit but prefer a thong. Plus, Reformation gets points for sustainability.

    Price: £14

  • Sweaty Betty – Mindful Seamless Hipster

    Sweaty Betty pants
    Sweaty Betty nail just about every other bit of fitness wear, so it shouldn't come as a surprise to learn that their pants are super comfy too

    If you’re after slightly thicker underwear (are winter knickers a thing?), then these Sweaty Betty knickers are the perfect choice. Also designed with a mid-rise fit, they’re available in three colours and the ribbed design means that the Seamless Hipster feels comfortable against the skin – whatever your activity.

    Price: £16

  • Thinx – Sport Brief

    On your period? No problem. Thinx’s Sport Brief replaces the need for tampons and/or pads, as they absorb up to three regular tampons-worth of blood. They might not be squat proof but with these knickers, you’ll never get caught out on your walk. Thinx also has a great size range.

    Price: £23.61

Best underwear for running and cardio

Cardio workouts, HIIT and running are the kinds of exercises that most require you to have comfy, breathable underwear. You’re likely to sweat more during these workouts – putting you more at risk of developing yeast infections.

Sweat can also cause uncomfortable itching around the bikini line, so underwear with less overall fabric and no details like lace or satin are ideal for cardio-based workouts.

  • Sweaty Betty – Barely There Thong

    Sweaty Betty Barely There Thong
    Sweaty Betty's thongs are guaranteed to stay in one place during the course of your long runs.

    Like the name suggests, this Sweaty Betty thong is made from minimal fabric so it doesn’t offer much coverage. But this is great for cardio, as it stays in one place so you’ll barely notice it as you’re running or doing lots of quick movements. It’s also made from a non-absorbent polyamide which means there is no pesky itchiness during or after workouts.

    Price: £14

  • Lululemon – Smooth Seamless Thong

    Lululemon Smooth Seamless Thong
    If you want a pair of pants that won't show under your leggings, Lululemon's place to go

    This thong is much like the Sweaty Betty pair above, but it offers a little bit more coverage if you like to feel a bit more secure. It also gets bonus points for being one of the thicker seamless thongs on the market which helps to prevent the transfer of odours between fabrics.

    Price: £15 

  • Nubian Skin – Classic Brief

    Nubian Skin Classic Brief
    Nubian Skin is known for its wide range of nude underwear – perfect for movers of all shades!

    Another great option for a seamless brief (which is ideal for cardio workouts) is Nubian Skin – a brand that is working to make the world of underwear more inclusive by offering a wide range of nude underwear in a variety of skin tones. These low-rise briefs are brilliant for running and wearing under tight leggings thanks to the fact that they also don’t create a VPL.

    Price: £16.50

  • THINX – Cycle Shorts

    What better way to ensure no VPLs than not wearing knickers at all? The THINX cycle shorts have a built in layer that means you don’t need to wear underwear with them, even when you’re on your period as the fabric is designed to be able to absorb up to two tampons worth of blood. These shorts, and the rest of THINX’s sport collection, takes squat-proof activewear to the extreme.

    Price: £55.34

  • Runderwear – Women's Running Briefs

    Rosie black original and brief
    Runderwear is renowned for this chafe-free, lightweight pants and bras.

    This list wouldn’t be complete without Runderwear – the original performance underwear brand. These briefs sit high on the waistline to offer exceptional comfort and support. You’re guaranteed chafe-free running, thanks to the seamless design, breathable and moisture-wicking construction and lightweight, technical fabric. Perfect for this Sunday long runs!

    Price: £18

Best underwear for strength training

Whether you are lifting weights or doing a bodyweight workout like pilates or yoga, strength training often involves bending, twisting and hinging – meaning that you need underwear that is really going to stay in place.

Crucially for strength training, you also need underwear that is squat-proof. The key to ensuring that your pants aren’t visible when you squat may be down to the quality of your leggings, but choosing the right kind of underwear can also help.

  • GymShark – Seamless High Rise Thong

    GymShark seamless high rise thong
    These thongs are thick enough to stay in place but are still seamless and squat proof.

    Thongs made from thinner fabric are great for running but something a little thicker will work better for strength training. That’s because thicker material is more likely to stay in place and (if you care) is flattering for all shapes. This GymShark thong is great because it still has the benefit of being seamless and squat-proof, but it’s made from a thicker material.

    Price: £12

  • Everlane – The Invisible High-Rise Thong/Hipster

    Everlane invisible high rise
    Everlane's brief and thong are both high rise and made from recycled material.

    The ReNew thong and brief are the most high-waisted of all the underwear featured. This high-rise fit, combined with added compression, makes both the thong and the brief really comfortable and helps to prevent VPLs. They’re also made from recycled materials – always a plus.

    Price: £17

Best all-round underwear

Although there are certain pairs of underwear that work better for particular styles of workout, you may not want to divide up your knicker drawer based on the activity you’re planning on doing each day. Or maybe you’re exercising in a way that combines all of the above exercises. 

Whatever your workout regime, here’s our selection of the best all-rounders.

  • Lululemon – Soft Breathable Thong

    luluemon soft breathable thong
    We guarantee that you'll forget you're even wearing any pants in these Lululemons.

    The LuluLemon Soft Breathable Thong is so soft that you’ll feel like you’re not wearing any underwear. In fact, we guarantee that when you do remember, you’ll spend five minutes marvelling at how comfortable you feel – which is really the aim of the game when it comes to workout pants!

    Price: £15

  • Uniqlo – Airism Ultra Seamless Hiphugger Briefs

    Uniqlo airism ultra seamless hiphugger briefs
    Soft and cool against the skin, this pair is also quick-drying and moisture-wicking.

    If you prefer a brief to a thong, you won’t do much better than this Uniqlo pair. Uniqlo’s AIRism technology is designed to feel soft and cool against the skin, with quick-drying, moisture-wicking and odour-control properties. You don’t need to worry about a VPL with these knickers either as they’re seamless.

    Price: £7.90

Ready to work up a sweat? Hop on over to the SWTC video library where you’ll find a range of 30-50 minute workouts, led by our very own trainers. 

Images: retailers’ own.

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