Every time you wash a load of synthetic activewear, it sheds tiny plastic fibers — and a lot of them. If you're trying to make cleaner everyday choices, learning how to avoid microplastics from your clothing is one of the higher-impact places to start, because workout gear is some of the most plastic-heavy fabric most of us own.
How much are we actually talking about?
The numbers are genuinely striking. Research has found that a single household wash load can release millions of microfibers — estimates range from roughly 6 million to 18 million from one 5–6 kg load of synthetic laundry. Those fibers flow out with the wash water, slip through treatment plants, and end up in rivers, oceans, and increasingly, in us. A 2025 Stanford Medicine summary noted that microplastic exposure may drive biological effects like inflammation and cell damage — the science is still developing, but the trend lines are enough to take seriously.
It's mostly about the fabric — and the dryer
Polyester, nylon, and acrylic are the main culprits, because they're plastic to begin with. How a garment is knit and twisted affects how much it sheds, but the single biggest avoidable amplifier is heat: tumble drying has been shown to increase microfiber release by around 3.5x compared to washing alone. So your dryer isn't just hard on your clothes — it's a microplastic multiplier.
Five practical ways to reduce microplastics from your clothes
1. Buy fewer synthetics where it counts. You don't have to purge your closet. But when you replace high-use items like leggings and base layers, choosing natural or wood-based fibers (TENCEL lyocell, organic cotton, merino) takes plastic out of the part of your wardrobe that touches your skin and gets washed most.
2. Wash less, and wash cool. Activewear often needs a freshen-up more than a full hot wash. Cold water and fuller loads (less friction per garment) both cut shedding.
3. Skip the dryer. Air-drying alone removes the biggest single source of fiber release — and your clothes last longer, too.
4. Use a filter or a bag. A microfiber-catching laundry bag or an in-line washing-machine filter physically traps fibers before they leave. France now requires filters on new machines for exactly this reason; you can add one voluntarily.
5. Choose quality over fast fashion. Cheaper, looser-knit synthetics tend to shed more and wear out faster, sending you back to buy again. Better-made pieces shed less and last longer.
The bigger picture
None of this requires perfection. The point isn't to feel guilty about the gym clothes you already own — it's to make the next choice a little better. The same logic runs through everything we do at Boda: the plastic in your leggings and the plastic in the ocean are the same problem, and the fix is the same too — choose materials that weren't plastic to begin with, and treat them well.
Today's small choice: Air-dry your next load of workout clothes instead of tumbling it — it's the single easiest win here.
Sources: Scientific Reports — washing & microplastic pollution; EWG — Does your laundry shed microplastics?; Green America — The plastic in your clothes.