Most people can tell you what's in their food. Almost nobody can tell you what's in their leggings. Here's what's actually on the label of the activewear most of us wear every week — and why it's worth a closer look.
Plastic doesn't breathe. Activewear should.
Did you know most activewear leggings are 85–100% nylon or polyester? Both are synthetic fibres made from petroleum, not plants. It's easy to miss because the label is small and the marketing rarely mentions it — but flip any pair of leggings inside out and the fabric composition is right there.
What is polyester?
Polyester is PET — the exact same plastic used to make water bottles and food packaging. It's made from petroleum, then either molded into a bottle or spun into thread for your leggings. Cheap, durable, stretchy. Also non-biodegradable, and known to shed microplastic fibres into waterways every time it's washed.
What is nylon?
Nylon has its own footprint on the other end of the supply chain. Making it starts with adipic acid, and producing adipic acid releases nitrous oxide — a greenhouse gas with roughly 298 times the warming potential of CO2. Adipic acid production is estimated to account for around 10% of the rise in atmospheric nitrous oxide globally. It's not something you'll see mentioned on a swing tag, but it's part of what goes into every nylon garment.
Why it matters against your skin, not just the planet
It's not only an environmental question. Heat and sweat during a workout can increase how much your skin absorbs from what's touching it — which is exactly the condition you're in while wearing leggings at the gym. We wrote more about the research behind that in this post if you want the detail.
The truth: some synthetic is doing real work
100% cotton can't four-way stretch and move with you the way activewear needs to. A small amount of synthetic thread is genuinely what gives a legging or a sports bra its stretch and recovery — that's not spin, it's just fabric science.
So we're not claiming zero synthetic. Our collection is 90% organic cotton, 10% polyester. That 10% is doing the structural job it needs to. But it's still roughly 90% less synthetic than most activewear on the market — less petroleum-based material, less microplastic potential, and a composition you can actually check for yourself.
Shop the organic activewear collection — shop now →
New here? Start with Is Your Activewear Plastic? for the full picture, including what sweat does to synthetic fabric against your skin.
Sources: nitrous oxide emissions from adipic acid (nylon precursor) production — C&EN, American Chemical Society; "Nylon production: an unknown source of atmospheric nitrous oxide," PubMed.