Written by James Poole –
The launch of the Adidas Ultra Boost has prompted me to pull my finger out and write a short review about my experience running in the Adidas Adizero Prime Boost. Given this shoe has been out since April last year, I am late to the party and as such I will eschew with all the various tech talk around the Boost midsole and Primeknit upper. Let’s be honest, there are plenty of shoe reviews out there that add no other value that to regurgitate what’s on the manufacturers website. This doesn’t intend to be one of them, so I will simply link you to the Adidas website for all the technology loveliness.
The Adidas Prime Boost is my first experience of running in an Adidas shoe. I don’t know why I’ve never tried them before, I just haven’t. Coming from the Nike Hyperfeel (with the rather spongy innersole ripped out) I’ll admit I wasn’t looking forward to running in a shoe with quite a lot more structure than I was used to. I am also keenly aware that my legs don’t like a lot of cushioning. A brief relationship with a pair of Nike Free 3.0 Flyknits ended with a rather unpleasant calf niggle that instantly went away when I switch to something less marshmallow-like.
So, in summary, the stage was set for disappointment. And initially my fears were realised. While the Primeknit upper is luxurious, glove-like and beautifully well made, I found the mid sole rather stiff and unforgiving. Its rigidness, presumably caused by the Torsion System in the mid-foot, created some soreness in my plantar fascia and the first couple of runs were not exactly a joyous PB busting sojourn.
However, after several more runs and some tweaks to the lacing I started to warm to the shoe. Firstly, it has a surprisingly wide toe box which allows the foot to spread naturally on impact. On the downside, I also feel that this width continues along the mid foot to the heel cup and this is where I was getting problems. The stiffness of the Torsion System meant that I was getting a tiny bit of heel lift in the propulsion stage of the running cycle. This was remedied using the top lace holes which produced a snugger fit across the top of the foot.
With the fit sorted, I was soon knocking out some decent mileage in the shoe. Between the beginning of December and the end of January I have clocked up more than 200 miles in a pair so now feel well placed to provide some sort of qualitative review.
Firstly, the Boost midsole really is something special. In the past I’ve stayed away from shoes that advertise themselves as having a blown EVA midsole. I’ve always felt that EVA provides little or no proprioception. You wouldn’t run with your eyes closed, so why run and not be able to feel the ground? By replacing the EVA with the Boost midsole material, I believe Adidas have found the perfect balance between cushioning and feedback. The sole definitely seems to return some energy in the propulsive faze and there seems to be a tiny amount of toe spring which aids a quick turnover. In short the shoe feels lively and quick; exactly the characteristics one would expect from a racing flat.
Secondly, the Primeknit upper is a thing of luxury. Its one piece construction hugs the foot where needed but also flexes easily through the forefoot. After some decent mileage there is hardly any signs of wear and while the retail price on the shoe is fairly high these look to be a shoe that will last for many hundreds more miles – a fact that is not true of some other lightweight racing flats I have owned.
Finally, there should be a few words on the outer sole. Having spent the last few months avoiding drain covers and slowing on corners while running in the Nike Hyperfeel, the outer sole on the Prime Boost is a breath of fresh air. With rubber supplied by Continental (of German tyre manufacturing fame) the shoe has plenty of grip and, so far, seems to be fairly wear resistant.
In the interests of transparency, I was fortunate enough to be given a pair of Prime Boosts by Adidas UK as part of their support of AdventRunning. However, it soon became apparent that this could be my shoe of choice for the Boston Marathon in April and I have since purchased the Limited Edition Consortium version of the same shoe with my own hard-earned cash. With the Ultra Boost dropping in the next couple of weeks and reports of the Takumi Sen receiving the Boost treatment for 2015 I’m excited by Adidas’s shoe options for the coming season. From 5km Park Run, to long marathon training or a sub-3 attempt at Boston it looks like Adidas have all the bases are covered.