Product Colors and Sizes

  • Black Friday product
  • New Deal product
  • Cyber Monday product
  • Clearance product
  • Deal product
  • Best Seller product
  • Ecodesign product
  • New product
  • Staff Pick product
  • In The News product
  • Innovation product
  • product

Kalenji Seamless Running Boxers, Men's

Sale price: $10.00 Regular price: $16.99

1-piece boxers (seamless) for maximal comfort and support. Ventilated areas for enhanced breathability.

Color: Select a color
Size: Select a size
Size Guide
Sale price: $10.00 Regular price: $16.99

Free shipping over $49

Final Sale: No returns or exchanges

Free returns

Free pickup

San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8488450

Product Features

A photo of the Kalenji Seamless Running Boxers, Men's in use

Kalenji Seamless Running Boxers, Men's | Our team of running enthusiasts designed these boxers for runners seeking improved performance.

1-piece boxers (seamless) for maximal comfort and support. Ventilated areas for enhanced breathability.

Moisture wicking

Fabric absorbs, diffuses, and dries quickly. Ventilated areas at the groin

Irritation reduction

The use of seamless technology reduces chafing.

Questions & Answers

Product Customer Reviews

Skip to reviews
1781 Reviews
Write a Review 

Kalenji Seamless Running Boxers, Men's,antique blue
Filtered by reviews Loading reviews…
BEST running underwear...need more in stock

I've loved these for years! It's such a shame that they haven't been in stock for such a long time! The seams in others always cause me painful chafing, but these have allowed me to run pain free! Please bring these back!

Sizing wrong

Very confusing sizing. On ask the items

icon-circle-checkmark verified purchase
tight, comfortable, breathable,seam free(almost).

Please get XXL sizes. I normallly wear L but even the XL of which I got of these is tight. Great for sport/active, but otherwise a larger(XXL) size would be perfect. The most seam free truck I've ever found( i've looked). They only have a small half-seam across the perineum. Would buy more of these if there was a larger size.

icon-circle-checkmark verified purchase

I love these. I have so much trouble with underwear for running and these are brilliant. I had to go one size up, normally M and got an L, and they fot perfectly.

icon-circle-checkmark verified purchase

Hi Adam

Thank you for your review and we are glad to hear that you are delighted with the product! We take feedbacks and reviews into consideration as we strive to make better products for all sports users out there! This product has ventilated areas to ensure breathability and comfort for users.

Feel free to view our website for more products or drop by to our nearest Decathlon store to you to check out more sports products catered for sports users!


Omni-Channel Sports Advisor

Decathlon Singapore

Really disappointed

I've loved everything I purchased from Decathlon, especially the running gear so I gave these a shot. They are super tight on the legs, the band folds over and there isn't really any frontal support.

Running Underwear

Great fit and very comfortable on runs.

icon-circle-checkmark verified purchase
Great fit

Great fit, comfy , really good fit easy to wear when running in leggins or working out in the gym.

icon-circle-checkmark verified purchase
Very comfortable

Sizing was perfect, comfortability outstanding

icon-circle-checkmark verified purchase
Good value

If 32 - 34 waist get extra large.

icon-circle-checkmark verified purchase
poor sizing

I have purchased underwear from decathlon in the past and had no problem with sizing. This product is grossly under sized. I would estimate you would have to go up 3 sizes to get them to fit. I would say the underwear looks a good quality, but I would not be able pass judgement on comfort, as would not of been able to get them.

Great underwear

Would recommend- well-fitting and comfy

icon-circle-checkmark verified purchase
Stopped my chafing!

I read the reviews and saw the comments about the seam, which is small and where the legs come together. However, this has caused me no problems and I have bought a second pair. The boxers have stopped my chafing, provide good support where required and feel good on the legs (I have tree trunk legs from my rugby playing days). Plenty of stretch and support.

Shocking - words can not explain

I am a fairly serious runner. Wore these once. Nearly ruined me. Never been in so much pain in my life. Truly unbelievable. Very very dissatisfied with this product. Pls consider carefully prior to purchase.

Pity about the seam

There is a totally unfinished seam in a very critical point in the crotch. Wearing inside out partly solves the issue, but the legs then roll up and causes other chafing. I love Decathlon, but this product is a fail.

icon-circle-checkmark verified purchase

Hello Rob,

Thank you for your review of our Kalenji Running Boxer. I'm sorry the boxer is not suitable for use. I have noticed that we have received a small number of reviews relating to the position of the assembly seam. The team will continue to monitor this situation. I propose that you return the model purchased, at your convenience -


Comfortable and supportive

Excellent product.... bought a trial pair in Spain, now bought more because I’m impressed! As good as, and much better value than, the expensive branded ones I’ve been buying. Highly recommended!

icon-circle-checkmark verified purchase
Skip to reviews

Size Guide

Size Guide Visual

Additional Product Information


Main fabric

  • 14% Spandex
  • 43% Polyamide
  • 43% Polyester cationic


  • 22% Spandex
  • 78% Polyester cationic



Product testing

These boxers have been tested in the lab and in use in the field by athletes of all levels. They were chosen by all our testers for their capacity to provide comfort during running in warm weather. Flat seams prevent chafing.

Superior quality. Unbeatable prices.

For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.

Decathlon makes the difference
  1. product-research

    Research and development

    delivers high-quality cost-effective products

  2. State-of-the-art production processes

    minimize manufacturing costs

  3. Optimized supply chain

    reduces retail prices

  4. laptop-checkout

    Minimal retail footprint

    lowers overhead and indirect costs


Size Guide Visual

Please Sign In to Post Your Question

In order to notify you about the answer it is required to Sign In.

Sign In