My local running store hosted a meeting with our running club and Adidas to try their new shoe, the boost. It was an entertaining evening and we got to have a short run in the new shoes.
The new foam
The Adidas boost uses a new type of foam in the sole that has more bounce and is more resilient. Adidas demonstrate the extra bounce by dropping a steel ball on their new foam and EVA, the industry standard foam. The ball will bounce much higher on the boost foam than EVA. However, it’s unclear how this will translate into running performance. When running, our feet do not bounce off the ground, but have a short period of sustained contact, often called the ‘stance phase’. So when your foot lands, it seems that the boost foam would return the landing shock back up your leg rather than absorbing it, which is less than ideal. It would be good to see a study that looks at how the boost foam changes the stresses on knees and hips compared with a standard running shoe. Regardless of how the bounce impacts your running, the increased lifespan of the new foam is appealing. Having a shoe that lasts longer is obviously good, but Adidas also claim that the new foam is more consistent through most of its lifespan, rather than gradually decaying in the way EVA does. Adidas also claims that their new foam does not change characteristics in extreme temperatures like EVA does.
The new shoe
So enough of the theory, what’s the shoe like? Well, the boost is clearly a mainstream running shoe, with the typical raised heel and front that does not mirror the shape of the human foot. If you accept that the boost is intended for that market segment, then it’s an impressive shoe. It’s immediately comfortable, with a light, flexible upper with no noticeable seams. Thankfully Adidas has used a traditional tongue and laces, rather than a sock style upper or Velcro fastening. While the sole has the traditional raised heel, there is none of the multi-density foam or other intrusions that are so common. The shoe is light weight, and the new foam is pleasant under foot. I think a lot of people will buy the boost because of its immediate comfort. The forefoot had good ground feel combined with reasonable protection. I’m not a big fan of the traditional running shoe, preferring either something minimalist or the maximum cushioning/minimal drop approach that has been made popular with the Hokas. However, if you’re in the market for a traditional running shoe, I’d highly recommend trying out a pair of the boost shoes.
I’m hoping that Adidas create other shoes based on the boost. If they simply reduce the heel height they’d have a great minimalist shoe without changing much else. If they widen the sole and increase the forefoot sole thickness they’d have a great ‘maximum cushioning/minimal drop’ shoe that would put the Hokas to shame.