Nike recently received a patent for so-called “architecturally reinforced denim,” paving the way for jean leggings and shorts that you can work out in. In the patent—reportedly its first ever claim for a jean product—Nike describes material made from “moisture wicking fibers and strengthening polymer fibers in combination with cotton fiber.” In non-tech speak, that likely translates to a stretchy, maneuverable fabric that resists easy tearing while managing sweat.

The Oregon-based sportswear giant brags that the “ath-denim,” as the internet has christened the innovation, will be comfortable on the skin while still providing protection from the elements. Nike says it was inspired to create the fabric for extreme sport athletes like sand boarders and BMXers, who require specialist gear but also want to look good. No images of apparel made from the denim are currently publicly available.

“This is Nike’s way of combining something mainstream with something more technical,” says Christopher Svezia, analyst at Wedbush Securities. “The vast majority [of their customers] buy for fashion and not function, but everything they do is embedded in sports.”

The patented “ath-denim” is designed to be incorporated with padding for the calf, thighs and bottom area. Indeed, it seems primarily designed for use waist down: the patent filing describes pants, shorts and skorts as the products Nike is interested in manufacturing.

Svezia doesn’t think that the denim activewear is necessarily a groundbreaking innovation., especially if consumers end up using it as a super stretchy lounging pant instead. Indeed, brands from Vetements to Topshop have been trying to reinvent a century-old fabric, sometimes with fashionably questionable results. “But is it part of an evolution to create what’s next? Absolutely,” he says.

A rep for Nike didn’t return a request for comment. The company also says it may use the patent for tops and associated apparel like shoes and hats “suitable to be worn during the practice of extreme sports, or during the practice of highly physically demanding activities.”

Nike had a rough past financial year as it comes to terms with the savvy of nimble competitors like Adidas and Lululemon, who have chipped away at its lead in the athleisure market. That said, 2017 has been better for the brand. Revenue in the latest reported quarter rose 5% to $8.43 billion, though the stock hasn’t been doing well. Investors are counting on chief executive Mark Parker to unveil new fashion-forward and innovative materials to protect Nike’s dominance in the burgeoning athleisure sector, which was valued at $270 billion last year.