Wearing a pair of Allbirds, you get a warm, fuzzy feeling. And that’s not just thanks to the supple material from which they’re made, but also the knowledge that the shoes are eco-friendly, too.

The San Francisco brand prides itself on using renewable natural materials and keeping its carbon footprint as low as possible.

Its first launch was into the casual sneaker section, its tagline ‘The World's Most Comfortable Shoes’‎ a clear line in the sand.

Slip on a pair, and you quickly realise this is not just marketing spiel; they are genuinely as soft as a pair of slippers, but with far more bounce and breathability.

The latter comes from the use of merino wool, which both regulates temperature as well as wicking away sweat.

They also come in a fibre made from eucalyptus pulp. It’s one of the most sustainable materials on the planet – not to mention incredibly silky to the touch.

Having conquered the everyday market, Allbirds has now launched its first running shoe, the Tree Dasher.

Entering the performance shoe market is new territory for the brand, but it’s stepped up its game.

The new trainers feature a lightweight one-piece upper made from FSC-certified eucalyptus trees, which not only has cooling and breathable properties, but uses 95% less water to produce than traditional footwear materials.

The upper also has an anti-microbial Merino wool lining to keep the foot cool.

The dual-density midsole is made from SweetFoamTM, Allbirds’s carbon negative green EVA solution, which is derived from renewable sugarcane.

And the removable sockliner is made from the castor bean plant (which emits less carbon than petroleum-based foam), and is contoured to provide flexible, anatomical support.

Allbirds is the embodiment of a challenger brand – in all senses of the term

Allbirds is the embodiment of a challenger brand – in all senses of the term. It’s taking on a $50bn athletic footwear industry, which largely relies on synthetic shoes made from oil-based plastics. In case it’s not obvious, we don’t like those.

Tim Brown, co-founder and co-CEO of Allbirds explains: “For too long, the performance industry told us that athletic footwear meant synthetic footwear. By failing to make the most of what’s right in front of us – nature – we've missed some of the greatest performance materials in existence.”

You may not see a pair of Allbirds on an Olympic athlete any time soon. But that’s not the brand’s MO. Instead, it wants to make everyday runners for everyday people – and avoid hurting the planet in the process.

For more information, see allbirds.co.uk