Heliot Emil designer Julius Juul has cofounded 444, a new activewear brand launching Wednesday with a 14-piece collection produced in Italy and Portugal, in a direct challenge to the synthetic fibers that dominate the performance apparel category.

Juul cofounded the label with Davide Maccari, whose background spans finance, fashion, design, neuroscience and endurance sport. The first drop, "Uniform 001," contains more than 95 percent natural or bio-based fiber content, according to the brand — a claim that positions the venture against an industry where polyester accounts for roughly 59 percent of global fiber production, and close to 90 percent of that is virgin fossil-based.

"Activewear sits well above that average, because stretch and moisture management have been engineered almost entirely around polyester, nylon and elastane," Juul told WWD.

The fiber architecture is material-specific. Eucalyptus-derived lyocell and wool form the foundation of T-shirts and base layers. Corn-derived fibers provide structure for compression pieces. Hemp, silk and cashmere appear elsewhere in the range. Trousers, shorts and knitwear are synthetic-free; T-shirts, socks and some compression pieces retain small percentages of elastane for stretch.

Juul set a concrete target on that residual synthetic content: "Our goal is to bring that to zero within the next two years, as bio-based alternatives reach the same performance."

Redefining performance criteria

The two-year development process led the founders to question how the industry measures performance. Rather than optimizing only for stretch, sweat-wicking and drying speed, the brand assessed temperature regulation, odor resistance and durability after hundreds of wears.

"When you train in natural materials every day, you notice other things [such as] temperature regulation, how a garment smells after a session, how it feels on day 300 rather than day one," Juul said.

The origin story, as Maccari frames it, was a "personal contradiction." He and Juul tracked sleep, recovery and nutrition while competing in Ironmans and ultramarathons, yet paid little attention to the garments they trained in.

"We come from fashion and design, yet we never paid enough attention to the labels on the clothes we trained in. The closest thing to our skin was also the most disposable thing we owned," Maccari said. "When we looked for alternatives, the options split in two — natural materials that didn't perform or look right, or good-looking performance fabric made from plastic. We didn't think those should be the only two options."

DTC launch, hospitality volume strategy

444 is launching direct-to-consumer, but the brand has added a B2B channel to solve a familiar problem for natural-fiber startups: reaching minimum production volumes. It is supplying uniforms and guest kits to hotels and wellness spaces, a volume strategy that signals how small-batch bio-based supply chains typically need anchor customers beyond retail.

Sustainability claims extend to packaging. Labels, hangtags and packaging use bio-based materials including paper and silk, with no conventional plastic.

Whether the venture can scale bio-based stretch alternatives to replace elastane entirely within two years — the timeline Juul has set — remains the open commercial question. The founders' approach, as Juul put it: "We let the material decide the product."