Adidas has taken the wraps of its latest technological running innovation, the Adidas Ultra Boost.
Claimed to offer more bounce than the first generation of Boost, more flexibility and overall to be the best runner yet, Adidas has a lot to live up to.
We took them out for a good few miles, after walking in them for a day, to see how they hold up.
The smart sole
Unlike most running shoes, which use EVA in soles, Adidas uses thermoplastic polyurethane (TPU) in its Ultra Boost. These rice-like pieces are crammed together to create a sole that offers energy return from the impact of running, effectively pushing you forward. There's no denying they feel like walking on clouds when you first put them on.
We were worried the bounce would just push back up and start hurting our knees, but this was not the case. In fact nothing hurt at all for the entire run. Despite the bounce we still felt balanced and controlled throughout. And in spite of the biting cold they remained pliable and flexible through the run. We've noticed EVA soles going hard in the past so this was refreshing to experience.
Adidas removed the EVA edge from the first Boost generation to offer 20 per cent more energy return. While you can feel the difference it also feels like you have more flexibility, which initially can seem like less support. But we had an ankle issue and despite worries it might not offer enough support it wasn't long before we had total trust that the shoe would do what we wanted as we ran.
The upper weave on the Ultra Boost feels like soft knit material to the touch and flexes when you slide your feet in. At the widest point of the foot it feels like there is enough expansion to let your feet spread and do their balancing work. But in the sides where you want support they remain tight.
The upper offers 4-way flexibility thanks to the way it was constructed. You can feel this as you turn and the shoe goes with you. Or more aptly you can't feel it, the Ultra Boost are so well matched to your feet you forget you're wearing them. And isn't this what running shoes should be all about? No blisters or even niggles were found despite doing a good few miles on a first run.
The ankle injury we mentioned previously resulted in a sore Achilles while running lately. Whether it's the shoe or the cold or something else isn't clear but we definitely noticed there was no pain while running in these. Adidas says it redesigned the heel to offer better Achilles support, cupping the foot all the way through the running movement.
The soft cushioning sole may have helped reduce impact that led to this comfortable, pain-free run, rather than just the heel alone. There is also a "dual-density Torsion System" that allows the heel to remain supported while the forefoot moves independently. Whatever it was, we were impressed as it worked.
We ran in the first Adidas Boost trainers and enjoyed them for the spring they added to our step, but they did sometimes feel a little tight in places. The Ultra Boost offer even more energy return while remaining invisible-comfortable and supportive. We've not done more than a half-marathon distance yet but Adidas claims the shoe will remain the same for hundreds of kilometres so we'd expect these to be a very wise investment for both short and long distance runners.