Fashion for Good’s The Next Stride project teams up with Adidas, Target, and Zalando to reinvent the shoe sole with bio-based materials, aiming to cut emissions and microplastics from the footwear you wear every day.
The part of a shoe that touches the ground is also the part with the heaviest environmental footprint. Fashion for Good is turning its attention there with The Next Stride: Bio-Based Materials for Footwear Soles, a year-long collaboration with Adidas, Target, and Zalando, alongside material pioneers Algenesis Labs, Balena, Evoco, Kuori, and Yulex. Together, they will test bio-based polymers as potential replacements for the fossil fuel-derived materials that currently dominate footwear.
For consumers, the shift could mean sneakers, sandals, and boots that feel just as resilient and comfortable but come with a far lighter impact on the planet. “The Next Stride is a critical, collaborative intervention to de-risk the widespread adoption of high-performance bio-based alternatives for footwear soles,” Katrin Ley, managing director at Fashion for Good, said in a statement. “By transforming the very foundation of the shoe, we address the most impactful component in its lifecycle and open the door to systemic change in the footwear industry.”
Why your sneakers carry a heavy footprint
Shoes are a $400 billion industry, and each pair leaves a surprisingly large mark. Studies estimate that footwear is responsible for about 1.4 percent of global greenhouse gas emissions. A synthetic running shoe alone can carry a carbon footprint of around 14 kilograms of carbon dioxide equivalent — roughly the same as charging a smartphone every day for five years. Around ninety-seven percent of that impact stems from raw material processing and manufacturing.
At least 40 percent of a shoe’s weight comes from its sole, and that concentration makes it one of the most damaging parts of the design. The industry standard materials — polyurethane, thermoplastic polyurethane, ethylene vinyl acetate, and rubber — offer durability and performance, but they are fossil fuel-based and rarely recyclable. They also contribute to another hidden problem: microplastics. As soles wear down, tiny particles are shed into soils, waterways, and even the air in our homes.
Numbers help bring the scale into focus. One analysis estimated that producing an average outsole weighing about 160 grams results in 2.04 kilograms of CO₂e emissions. Across millions of pairs of shoes, those grams and kilograms add up. Another study of nearly 9,000 pairs of shoes put the average footprint at 35.58 kilograms CO₂e per pair. Even modest improvements in sole design could ripple out into major reductions for the industry overall.
Reimagining the foundation of every shoe
For Adidas, Target, and Zalando, this project is a chance to meet shifting consumer expectations. As Gudrun Messias, director of sustainability at Adidas, puts it, “sustainability and performance go hand in hand. Through The Next Stride, we will work with innovators to explore if bio-based materials can potentially lower the environmental impact of footwear soles while at the same time meeting or even enhancing the high-performance standards our athletes and consumers expect.”
That balance between sustainability and performance is what will make or break consumer adoption. A compostable sneaker means little if it cannot withstand daily runs or withstand seasons of wear. That is why the project is working with SATRA, a trusted testing partner, to rigorously benchmark durability, grip, and resilience against conventional soles.
Consumers are also voicing a clear desire for greener options, though the gap between aspiration and action persists. Zalando’s VP of sustainability, Pascal Brun, points to research in its It Takes Many report: “Consumers aspire for more sustainable choices. We believe innovation in materials is key to meeting that demand. The Next Stride brings together the right partners to reimagine the sole, the foundation of every shoe, and set new benchmarks for the industry.”
The challenges are real. Bio-based polymers often face questions about scalability, feedstock sourcing, and competition with food crops. Recycling infrastructure is still lagging. But material science is evolving fast, and more affordable, durable alternatives are beginning to emerge. For the average shopper, the outcome could be shoes that carry an environmental label with the same confidence as a performance one. Instead of choosing between a sneaker that lasts and a sneaker that’s sustainable, the goal is to offer both.
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