No petroleum-derived fibres. No microplastic shedding. No shortcuts.

Most sportswear is made from oil.

Not metaphorically. Literally. Polyester, nylon, elastane - the fibres that make up the vast majority of activewear on the market - are all derived from fossil fuels. They're plastic, engineered into fabric form, worn against your skin every time you move.

The industry has offered one answer to this: recycled plastic. Bottles and fishing nets spun back into fibre, marketed as sustainability. It's a better story than virgin synthetics. But it's still plastic. It still sheds microplastics every time you wash it. And it still comes, ultimately, from petroleum.

Underscored exists because we don't accept that this is the only way.

We are a British performance sportswear brand built from the fibre up - designed for women who play racket sports, and built without a single petroleum-derived fibre. Every material choice we make starts with the same question: can we achieve this without fossil fuels? If the answer is no, we go back to the drawing board.

That's not a marketing position. It's a design constraint we imposed on ourselves from day one.

Our Ashdown range is made from TENCEL™ Lyocell and SeaCell, natural and bio-based fibres that breathe, wick moisture, and move with you. No polyester. No nylon. No elastane. 100% plastic-free. 100% petroleum-free.

We are designed in London. Made in Portugal. Certified with 1% for the Planet and The Climate Label. And we believe we are the only performance sportswear brand in Britain built without petroleum-derived fibres.

Performance without compromise isn't a strapline. It's what happens when you refuse to take the easy route.

 

 

Is Underscored really plastic-free?

Our Ashdown range — TENCEL™ Lyocell and SeaCell — contains no plastic of any kind. It is 100% plastic-free and 100% petroleum-free.

 

What does "petroleum-free" mean in sportswear?

It means none of our fibres are derived from fossil fuels. The most common performance fabrics - polyester, nylon, and elastane - are all petroleum-derived plastics. We use none of them. Not even recycled versions. Our materials come from wood pulp and seaweed.

What fibres does Underscored use?

TENCEL™ Lyocell, derived from sustainably sourced wood pulp, produced in a closed-loop manufacturing process. Naturally breathable, moisture-wicking, and thermoregulating. Biodegradable.

SeaCell, a bio-based fibre incorporating seaweed. Soft against skin, naturally derived, and fully traceable.

Why does microplastic shedding matter?

Synthetic sportswear sheds hundreds of thousands of microplastic fibres every time it is washed. Those fibres pass through water treatment systems and accumulate in oceans, rivers, and food chains. They have been found in human blood, lung tissue, and breast milk. Because Underscored uses no synthetic plastic fibres, our garments do not contribute to microplastic pollution.

Isn't recycled polyester a sustainable choice?

It is a less harmful choice than virgin polyester in lifecycle terms. But recycled polyester is still polyester - still petroleum-derived, still plastic, and still shedding microplastics with every wash. Recycled synthetics are a marginal improvement to the same broken system. We think the fibre itself needs to change, not just where it comes from.

Does natural mean less performance?

No. TENCEL™ Lyocell outperforms polyester for breathability, moisture management, and comfort against skin during exercise. It is also more durable through repeated washing than many synthetics. The assumption that performance requires plastic is an industry habit, not a physical law. We built Underscored to prove that.

Where is Underscored made?

Designed in London. Manufactured in Portugal in small production runs, with full supply chain visibility. We chose Portugal for its manufacturing quality, proximity, and alignment with our values around responsible production.

What certifications does Underscored hold?

We are certified members of 1% for the Planet, contributing 1% of revenue to environmental nonprofits. Our carbon footprint is independently measured and publicly disclosed through The Climate Label. TENCEL™ Lyocell carries OEKO-TEX and FSC certification for its closed-loop production process.