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 Chafe free
//  Seamless
//  Moisture wicking
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INTERVIEW: Svenja Espenhahn and the Journey From Non-Runner to Ultra Running Star

INTERVIEW: Svenja Espenhahn and the Journey From Non-Runner to Ultra Running Star
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  1. How long have you been running? I started running around April 2016. Up until then, I rarely tried to run as I absolutely hated it and could not...

INTERVIEW: Adrien Prigent, Champion Ultra Runderwearer™

INTERVIEW: Adrien Prigent, Champion Ultra Runderwearer™
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We're proud that #Runderwearers all over the world wear our products, running chafe-free and in comfort; from jogging around the block to 100 mile Ultra Marathons.  We recently had the chance...

10 Top Tips For Running in the Summer

10 Top Tips For Running in the Summer
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Advice for running in the heat... The summer months are upon us - here are a few tips to help you run in comfort as the temperature warms up.

What is Chafing?

What is Chafing?
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What is chafing? Chafing is a friction-induced skin injury where the outer layer of skin (epidermis) is rubbed creating microscopic tears, exposing the skin layer below (dermis), which becomes red,...

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performance underwear
★ Read Our Reviews

Let customers speak for us

2408 reviews
Catherine Duff said: Runderwear Hipsters

The most comfortable underwear you will ever wear for sport...... what more needs to be said! Catherine

Teresa Kelly said: Good running pants!

Good pair of running pants, felt good whilst running and afterwards and a good fit! Very light, would definitely recommend them! I bought a medium and I’m usually a size 10, they didn’t feel too tight however I’m glad I didn’t go for a small as I can imagine the small would have been tiny! I only have cotton pants to compare with as these were my first pair of running pants I purchased but I was impressed! A lot of money but when it comes to running long distances it pays to pay for comfort.

Maria Martin said: Best pants ever.

I have already recommended these to other runners in my club because they are comfortable, the material is very soft and they do not move at all!!

Richard Parsons said: Fast Pants!

These undies are great. I’ve always run in cheapo cotton trader undies which are a sweat-soaked nightmare. Swapping to Runderwear is a revelation - comfortable, excellent wicking properties, light weight, no chafing, dry quickly. On first wearing I did a 10k personal best, so they’re christened as my fast pants! Well worth the investment and won’t look back.

Izzie said: WAY TOO SMALL

I ordered these in a size medium as I am a UK size 10 or a medium in all other underwear I own (Under Armour, Moving Comfort etc.). However, these are TINY. Like absolutely miniscule. I tried them on and they dig into my butt cheeks so bad its like I have 4 cheeks. Not good. I emailed Runderwear customer service to see if I can return them but I haven't heard anything back for several days now. Really not impressed at all with the sizing guide or the customer care considering one pair of these underwear costs so much.