The new Salomon Index.02 is a recyclable running shoe that builds upon the groundbreaking model the company introduced two years ago.
Like its predecessor, the Index.02 is 100 percent recyclable. It’s also 10 percent lighter, at 263grams. The Index.02 features upgrades in comfort and performance thanks to improvements in the midsole geometry, foam quality and upper construction.
Most notably, the midsole foam and midsole geometry of the Index.02 have been upgraded to deliver smoother transitions from stride to stride. The plush, long-lasting comfort is due to the use of a lightweight Infiniride foam. This TPU foam is the only fully recyclable foam. The weight of the Index.02 has been reduced from 288 grams to 263 grams (sample size US 9 Men’s).
The Index.02 has an updated upper with more colors, softer materials and premium finishes. Specifically, the upper uses Engineered Mesh, a structure that varies the weave to offer more support and breathability. It also offers better flexibility or durability, according to the specific needs of the shoe.
“The foam is less dense on the Index.02, so it feels cushier,” says Laurent Coudurier, Salomon Footwear R&D Manager. “We also removed some bits in the upper, bringing the shoe closer to the foot. Our goal is to provide the same level of performance as the rest of our road running shoes and we’re getting there.”
Life and Recycle
Like its predecessor, the Index.02 features a unique construction that allows it to be disassembled at the end of its life. This ensures that the shoe materials can be recycled to make a new product. A subtle line along the shoe shows where it will be split when it is recycled. Different colors on the upper and bottom highlight that it uses only two materials and can be separated for recycling. A QR code on the tongue of one shoe allows the shoe owner to easily scan and register it after purchase. This makes it easy to return for recycling. Like the Index.01, when Index.02 shoes are sent back for recycling in Europe, the materials will be used in the construction of Salomon alpine ski boots.
“We started researching materials for the Index.01 shoe about five years ago, looking to reduce its impact,” Coudurier said. “With this new Index.02 model, we’re getting closer to providing the same level of performance as the rest of our road running shoes.”
Analyzing for Research
To assess the environmental impact of the Index.01 recyclable running shoe, Salomon’s Footwear development teams compared the impact of the Index.01 with the Sonic 3 shoe from the brand’s road running range. By compiling and evaluating the inputs, outputs and potential environmental impacts through its life cycle, it is possible to clearly tell the impact of each step—in terms of carbon emissions, use of natural resources, water eutrophication from nitrates (caused by the cooling of machines and colorization) and water acidification, among other aspects.
“A life cycle analysis identifies the biggest environmental impact during the life cycle of the product, in order to work on reducing it,” says Olivier Mouzin, Footwear Sustainability Manager.
The way the Index.01 is made and the fact that it can be recycled reduces by 44 percent the amount of CO2 compared to a traditional shoe, which is 4.9kg of CO2 Eq less for every pair. The emissions from the lifecycle of the Sonic 3 are 11.2kg of CO2 Eq; the Index.01 emits 6,3kg of CO2 Eq. Water eutrophication is reduced by 70 percent, and water acidification is reduced by 35 percent.
“The Index.01 is a great start for sustainable footwear. We can test this new, simple design and its performance on the road, and test out the collecting and recycling process,” Mouzin said. “As the lifecycle analysis shows, the impact of the shoe is reduced by 44 percent, which validates our work and encourages us to develop more footwear products following this circular economy concept. Now, with the Index.02, we are continuing to improve the quality, comfort and performance of a fully recyclable shoe. It’s very encouraging.”
