Wednesday, September 25, 2013

First Review adidas adizero adios Boost: Light, Boost Powered Racer/ Light Trainer

Earlier this year adidas launched the Energy Boost featuring a midsole made of TPU instead of the conventional EVA. The Runner's World Shoe Lab found in an article by Amby Burfoot:

   "Yet after poking, prodding, stomping upon, dissecting and inspecting (under a microscope) the new     “boost” midsole, Martyn confirmed what Adidas is claiming: the shoe has “industry leading” energy return (more on this soon), thin and lightweight but effective cushioning, tremendous resistance to heat and cold, and more durability (perhaps twice as much) as conventional EVA midsoles. "

I am now on my second pair of Energy Boost and have found the claims above to be largely true. With the exception of some curling up at the toe and normal outsole wear my first pair with 300 miles feels and looks like new. The Boost material really holds up far better than conventional EVA. My review of the Energy Boost is here.

This said the Energy Boost is really a trainer. In October adidas launched the adizero adios Boost a Boost midsole version of their popular adios racer.
adios Boost

adios Boost is a light, 7.8 oz  Men's 9 US,  6.6 oz Women's 8 US  cushioned racer/trainer with heel/toe drop of 23/13mm vs. 26/17 for the Energy Boost according to Running Warehouse. This is not a low drop shoe but certainly runs like one for me. They fit me true to my size 8.5 with a light sock.

The adios Boost is just starting to be available in the US. I got mine from Wiggle in the UK earlier in September. Wiggle is a great place to get products released in Europe before the US  for very close to what they will sell for in the US and with very reasonable and rapid shipping.

Upper:
adios Boost (left) Energy Boost(right)
Unlike the Energy Boost with its stretchy soft shell "Techfit" material, the adios Boost has a conventional mesh.
The individual cells' weave is not particularly soft but as they are small and with entirely welded overlays in the toe box provide  a great combination of support and give.
The lacing goes far further towards the toe than in the Energy Boost.
The toe box is plenty wide for a racing shoe over the forefoot then somewhat pointy towards the toes. The tongue is thin mesh with minimal padding.


Midsole and Outsole:
The midsole is of course made of Boost. The construction is identical to the Energy except of course thinner at stack heights of 27.75/17.25mm vs, the Energy Boost with 31.5/21.5mm.


adios Boost Outsole
adios Boost Outsole
The outsole/midsole interface features the adidas Torsion System as on the Energy Boost, a web of thin, stiff  green plastic under the arch and extending in strips on the outer edges towards the toe. This system produces the snappy toe off and also helps stabilize the soft Boost material. It really works. In board are 2 glued on strips of small lugs: black outer sole covering tiny stiff pieces of plastic. Based on my first runs, these tinylugs help stabilize push off while giving good ground feel and providing more flexibility than solid strips of outsole would. Finally, a somewhat firmer than Boost material EVA torsion piece, ironically with the word "Boost" on it, is used in the heel for a firm yet cushioned heel landing and roll forward. The actual outsole is "Continental" rubber, as in Continental tires for claimed great slip free grip on all surfaces and long wear.





Flex:
This is one stiff shoe with a very springy flex point as illustrated in the photo (right). I was working hard to push down and flex the shoe. Some may not like this approach but I find it highly responsive at speed. The Energy Boost has a similar stiff flex but the flex point is somewhat further back than the adios. I can say that with close to 300 miles on my Energy Boost they have remained consistently stiff and I would expect the adios Boost to perform in a similar fashion. There is no break in with these shoes. The first miles will feel exactly like the last all around: cushion via Boost and flex and stability via Torsion.


Ride and Runs:
I have done 5 runs for a total of about 30 miles in the adios including a very brisk 7.5 mile tempo that included flats and steep uphills and downhills. In a word "incredible" at speed, less fun for a jog.  The adios have a great combination of snappy response and a cushioning that only be described as soft when it needs to be and firm when it needs to be. By this I mean the initial landing is soft but stable and the push off is firm, very directed with no sloppy feeling  with great ground feel and responsive rebound from the combination of Boost and Torsion. My tempo at altitude was considerably faster than expected and the next day my legs were none the worse for wear. With a marathon in 2 weeks with 2500 feet of downhill I will be cautious and run the Energy Boost but for any other race adios Boost for me!
Update: Ran my first race in the adios boost, the traditional, low key Gosport Chowder Club Huffin' for the Stuffin' 5K here in coastal NH and finished 3d overall. They felt great super snappy and firm but unlike other racing flats not harsh and jarring. Legs fresh the after the race and next day.
Update 2/2014: I have now done 3 long races in the adios Boost: 15K, Half, followed by a 20 miler the week after All three races have been surprisingly fast for me including a 1:37.42 half in cold weather, my first half under 1:40 on a legit course since 2011. Even the 20 miler yesterday was painless and I ran today with minimal soreness. The adios truly disappear on the feet, are snappy, and without removing road feel have a unique combination of race flat fast feel, great cushion and no harshness.

Pros:
Light, cushioned, highly responsive racing machine for distances from 5K to Marathon.
Boost material really works at speed when combined with the stability of Torsion
Expected long life of midsole for consistent performance over time.

Cons:
10 mm drop may put off some but I run in mostly 4-6mm shoes and didn't notice.
Toe box may feel narrow for some but after all this is a race shoe.
Stiff forefoot with highly directed push off, not particularly "natural" for some.
Price: Expected MSRP around $140.

Other reviews: Pete Larson at Runblogger reviews the adios boost and likes them a lot.
adios boost review at Believe in the Run. adios boost directly out of the box for a marathon!

8 comments:

Brad said...

Really nice review, Sam! This sounds like a great shoe, and you covered all the aspects very well. I'll be looking forward to hearing updates as you put more miles on the Adios. With your mention of the toe box feeling narrow, do you think this would keep you from using the Adios as a workhorse/daily trainer?

sam winebaum said...

Brad, thanks for reading my review and your question. I would have no problem using adios boost as a daily trainer given toe box. I have a somewhat narrow foot. I do mix in more substantial shoes such as the Energy Boost, Newton Energy, and Hoka Rapa Nui so adios would be my speed hard tempo and sub marathon race shoe. All 3 of my other current shoes have a somewhat wider toe box at least towards the toes where the adios narrows down.

Anonymous said...

Very helpful review Sam. Thanks. Do they provide some stability for mild over-pronators? Are you still happy after putting a few more miles on them? Mike

sam winebaum said...

Anonymous, I am still delighted with adios boost especially at speed. Do all my intervals in them and not only are they snappy responsive but legs are not sore day after compared to traditional race flats. There may be a bit of pronation support from the under arch torsion plates, between outsole and midsole but as far as the midsole it is all boost with no stiffer material as in a support shoe under the arch.

William Nee said...

Nice review! I'm a minimalist type guy, but decided to try these shoes out after reading Runblogger's review. Overall, it's a great shoe and a glimpse of the future, but the toe box is too narrow, and becomes uncomfortable on runs beyond 10-15 miles or so. I hope they fix this in later versions.

sam winebaum said...

William, thanks for reading my blog. At first I thought the adios would be to narrow but after a few runs ( 20 or so miles) they seemed to stretch. I do have fairly narrow feet and prefer a wide toe box. This said I sometimes find a wide toe box and slipping cause me blisters on long runs. So far in adios with longest run a 20 mile race zero blister issues or even hot spots. I swear by the Ashmei wool carbon socks.

Mike St. Laurent said...

Can't wait to get my hands on these. I am curious how long they will last and if it will prevent my legs from soreness.
LOCO Mike - Runner since 1969

sam winebaum said...

LOCO Mike, I have 130 miles to date on mine. Still plenty of rubber although some wear but this is after all more a racer than trainer so outsole is not super thick even if it is super durable. I think with help of some shoe goo down the road should get 300-400 miles out of them easily. Boost is not going to collapse and upper is plenty durable and like new.