Stella McCartney has teamed up with material science company Balena to launch the S-Wave Sport trainers.

Debuting as part of the Autumn 2025 collection, the trainers utilize Balena’s innovative material, BioCir Flex, a non-toxic, compostable, recyclable and biobased alternative to conventional plastics. 

Notably, BioCir Flex is made from sustainable sources like castor beans, oils, and polysaccharides. It is as durable as TPU and as flexible as rubber, and is dyed with natural cinnamon.

“I mean this is insane. My shoe designer came up to me and said, ‘smell the sole’. It’s made of cinnamon waste. It smells of cinnamon! And it’s basically 100% plant based, recyclable and biodegradable textile. Its a closed-loop production, so it ensures completely zero waste. It is mind-blowing,” Stella McCartney said in a statement. 

David Roubach founder of Balena Science, added: “This collaboration represents more than just a partnership—it’s a shared vision of a future where materials are circular, sustainable, and high-performance. Stella McCartney has always been a beacon of innovation and responsibility in fashion, and to see Balena’s material -BioCirFlex- integrated into her designs is a milestone I could only have hoped for when we began this journey”

The trainer will launch globally in April.