Borax Workout Clothes: How to Deep Clean and Remove Odor for Good

If you’ve tried everything to get the smell out of your activewear—but it still stinks—you're not alone. Workout clothes are made from synthetic fabrics that trap sweat, oil, and bacteria. Even with regular washing, that lingering odor can stick around. The solution? Try a borax soak for workout clothes.

Using borax on workout clothes is a simple, affordable way to deep-clean your gear and eliminate odor-causing buildup. This method has been around for decades and is now making a comeback—especially among those who live in Lululemon leggings, Alo sets, or wear activewear daily.

In this post, we’ll cover why borax works, how to do a proper borax soak, and how to keep your activewear smelling fresh going forward.

Why Workout Clothes Hold Onto Odor

Before we get into borax, let’s look at the root of the problem.

Workout clothes are typically made from polyester, nylon, or spandex—synthetic fabrics that are great at wicking moisture but not so great at releasing oils and bacteria. Over time, your leggings, sports bras, and tanks collect:

• Sweat

• Body oils

• Bacteria

• Detergent and softener residue

Even premium detergents may not fully break down this gunk—especially if they’re not formulated for synthetic fabrics. That’s where a borax soak for workout clothes comes in. It targets this buildup and resets your gear.

What Is Borax?

Borax (sodium borate) is a naturally occurring mineral used in cleaning for over a century. It acts as a laundry booster by:

• Softening hard water

• Breaking down oils and grime

• Removing odor

• Enhancing detergent performance

When used correctly, borax on workout clothes helps strip away what your regular wash routine leaves behind—without damaging fabrics.

Benefits of Using Borax on Workout Clothes

Here’s why people swear by borax for their gym gear:

• Neutralizes odor – Borax breaks down the bacteria that cause the “sweaty smell”

• Lifts residue – It removes detergent build-up and fabric softener coatings

• Restores softness and stretch – Your clothes feel more breathable and flexible after a soak

• Affordable and effective – One box lasts a long time and costs less than fancy cleaners

Whether you’re dealing with old leggings that smell musty or sports bras that stink after one wear, borax workout clothes soaks are a powerful refresh.

How to Do a Borax Soak for Workout Clothes

Ready to try it? Here’s a simple, step-by-step method for soaking your workout clothes in borax.

What You’ll Need:

• A bathtub, sink, or large basin

• 1/4 cup borax

• 1/4 cup washing soda (optional, for extra cleaning power)

• 1/2 capful of liquid detergent made for activewear (like Sweat Chemistry)

• Hot water (enough to fully submerge your clothes)

Steps:

1. Fill your tub or basin with hot water

2. Add borax (and washing soda if using) and stir until dissolved

3. Add your detergent and mix again

4. Submerge your workout clothes, making sure they’re fully soaked

5. Let them sit for 4 to 6 hours, stirring occasionally

6. Drain, rinse thoroughly with cold water, then run a short cold wash cycle with no detergent

7. Air dry flat or hang dry in a ventilated area

What to Soak (and What Not To)

✅ Safe for soaking:

• Leggings

• Sports bras

• Workout tops

• Athletic shorts

🚫 Avoid soaking:

• Wool or silk

• Delicate lace or embellished items

• Anything labeled “dry clean only”

Borax is safe for most performance fabrics but always check garment tags first.

How Often Should You Borax Soak Workout Clothes?

You don’t need to do a borax soak for workout clothes every week. Once every 1–2 months is enough to reset your gear—especially if you’ve used fabric softeners or mainstream detergent in the past.

If your clothes:

• Smell even after washing

• Feel heavy or waxy

• Don’t seem to breathe like they used to

…then it’s probably time for a soak.

How to Keep Clothes Fresh Between Soaks

After you’ve soaked and reset your gear, follow these tips to prevent buildup from coming back:

• Use a liquid detergent made for activewear, not generic formulas

• Wash in cold water on a gentle cycle

• Turn clothes inside out before washing

• Skip fabric softeners and bleach

• Air dry or use low heat if using a dryer

• Wash gear as soon as possible after sweating

Following this routine keeps your clothes cleaner for longer—so you won’t need to rely on stripping or soaking nearly as often.

Final Thoughts

If you’ve been asking, “Why do my workout clothes always smell?”—a borax soak for workout clothes might be the answer. Borax helps break down trapped bacteria, sweat, and product residue, giving your gear a second life.

Pairing it with a detergent made for synthetics (like Sweat Chemistry) helps maintain freshness and performance between soaks. Don’t toss your favorite leggings just yet—soak them, rinse, and start fresh.