I’ve had a pretty long history with the adidas adizero XT line, having run in all of the XT models except for the first one (still keeping my eye on eBay for a pair). The shoes have evolved somewhat from the XT 2 and 3, which had a very versatile, all-mountain outsole that still runs super smooth on trails. XT 4 was more of a fell/mountain shoe with a fair bit of structure to it, and the XT 5 (review here) ran more like a marathon racing shoe with a few trail specific additions. The XT Boost sets out in uncharted territory with a completely unique upper design, and the addition of Boost for the first time in the XT line. Read on to see how it turned out. Discolsure: The shoes were provided free-of-charge for review by adidas.
Specs
Price: $140
Weight: 260 g (9.2 oz) size 9 men, 230 g (8.1 oz) size 8 women
Stack Height: 29mm Heel/18.5mm Forefoot; 10.5 mm drop
Specs from adidas
Fit is pretty typical of adizero lineup and just how I like it. Snug heel and midfoot with a medium toebox.
Gaiter is neither too tight nor loose, and is effective at keeping stuff out.
Upper and Fit
The XT Boost sports one of the most unique uppers on the market today. When I first saw the shoe, I was a little leery of the upper and figured it would either work really well, or completely ruin the shoe. After putting some miles on them I can say that I really appreciate the upper, and feel it is a real asset for the shoe. For example, sometimes I’ve reached for the XT Boost when heading out on a run simply for the extra coverage the built-in scree gaiter provides. It keeps all debris out in the mountains in the summer and fall, and even did a pretty good job with a recent run in 3 inches of fresh snow (although the rest of the shoe is not intended for winter and is pretty breathable).
Aside from the gaiter, which is great, the rest of the upper checks most of the boxes for me and fits like most adidas in the adizero line (i.e. pretty close to the adios in fit – same last I believe). The shoe is randed from the forefoot through the midfoot, holds the foot pretty well, and is sufficiently breathable. It is not as seam-free as I’d like, but I still haven’t had any issues running in them up to 2.5 hrs without socks.
As an aside, adidas was planning on releasing a Primeknit version of the XT Boost with a full knitted upper – I was drooling over it, but unfortunately it was canceled before release. Such a shame and I sure hope they reconsider releasing that shoe at some point! Overall though, the upper on the XT Boost is a great example of a company trying something new, in a thoughtful way, and I think it pays off with a very unique and effective end result.
Great midsole with adios style geometry, Boost in forefoot and a unique randed, yet simple upper.
Midsole and Ride
adidas usually excels in this area for me, and the XT Boost is no exception. The XT Boost keeps a more marathon shoe midsole geometry like the XT 5, with a 10.5 mm drop (really 6mm would be ideal, but not a huge problem) and a pretty low forefoot stack height (similar to the adios). The ride is quite different from the XT 5 though, and even from the adios Boost for that matter. While still racy and fairly precise, the XT Boost is softer, less structured and more flexible than either of those shoes. It’s still protective enough for 50k, and maybe even up to 50 miles if one is used to lighter footwear.
With Boost just in the forefoot, it creates a more specific feel to the shoe with a firmer rear half and a responsive but more forgiving forefoot. I usually like the opposite (firmer forefoot/softer heel), but I think in this case it works pretty well since Boost is still responsive, but gives the forefoot a good deal of flexibility which helps when climbing and on technical terrain. The heel shape is probably the only area I’d tweak on the midsole. I simply think it is too wide and bulging. They could keep a narrower heel design and not lose any stability or ride quality. Other than that, even though I never had protection issues, I’d like to see a thin rock plate/torsion shank (like in the Terrex Boost, but quite a bit thinner) in the XT Boost. I think the extra protection and structure provided by a rock plate for long runs is worth the weight tradeoff. If the shoe was sub 8 oz., I might reconsider (although I like rock plates a lot :)).
You can see the bulge of the heel design. One of the few things I don’t like about the shoe as I think it should cut pretty straight down following the line of the heel counter rather than flare out, especially in a shoe this light and nimble; it only gets in the way when side-hilling and on the downhill. Doesn’t ruin the ride, but could improve it if altered.
Outsole
adidas’ partnership with Continental has been around for awhile, but I feel the new round of trail offerings for both 2015 and the forthcoming 2016 lineup are the best yet. They are simple in design, full coverage, black rubber, with repeating lug patterns that run well while providing market leading grip. The XT’s outsole is the most low profile of all the adidas trail offerings, yet is still pretty aggressive overall, and I would consider it to be an all-mountain type outsole. It has the ability to run well on both trail and in the mountains/off trail while not firmly in the Trail or Mountain category. These types of outsole setups are particularly great for routes that have you starting low on smoother trails and finishing on a peak or with off trail sections up high. This outsole would be perfect for a race like the Rut 50k that I did last year where there is an equal mix of smooth single track and rugged off trail since it would not be unpleasant on either. If you are looking for outsoles that provide great traction on a variety of surfaces, but don’t get in the way on smooth trail, the XT Boost, Terrex Boost and Response Boost have some of the best out there.
Great outsole design as with the rest of the recent adidas trail lineup. Don’t think they need to expose the Boost in the forefoot, but doesn’t hurt it a ton. Lug depth might be a tad much for this shoe, but adds to the versatility, especially with the gaiter on the upper.
Conclusion
Not much else to say. I really like the shoe and it ranks as one of the best I’ve tried all year. I’ve been wanting trail shoes with marathon shoe geometries for quite some time and the XT Boost is one of the few shoes that provide that in the current market. The fact that they do it in a shoe with such a unique and effective upper even further sets it apart. It rides like a mix of the adios Boost and to some degree the Takumi Ren 3 (which also only has boost in the forefoot), and has great traction for a wide range of conditions. It also runs decently even on the few road sections I’ve been on with it. If you’re looking at a trail shoe on the lighter/faster end of the spectrum, this is the first shoe I’d recommend.
The adidas adizero XT Boost is available for purchase at Zappos in the US and Wiggle in the UK.
About David Henry
looks like it might be great on snowy trails add some screws and your good for ice and traction
I wouldn’t recommend it for snow specifically since it is pretty breathable mesh even on the gaiter and I’m not sure the outsole is thick enough for screws. There are going to be some more winter specific shoes coming out next year with integrated gaiters that I’d save for that purpose or look to something like the La Sportiva Crossover GTX. The XT Boost is much more of a Spring-Fall trail/mountain shoe. -David
Hi David,
Im waiting for your new mountain shoe review as I’m looking for some new and better “wings”. (Ill try this media to get in contact as it seems pretty hard to find any other way :-) respect to that!)
I need your help to sort out a few newcomers or (g)oldies to buy?!
I run up to 50K training and races, mostly mountain trails, which can be from dry n stony to wet n dirty. Feet are neutral and arch normal/high. I like the heel to be tight and midshoe tight/medium and pretty flat/medium toe box. Drop around 4 mm.
Ive tried Inov-8 212 and S lab fell cross and sense ultra. I know you’re not a big fan of Salomon ( they kinda fit my feet well though ) but I’m openminded and would like to hear if you have any ideas?
Priorities for me would be in order: a great fit and feeling (need some pairs to try on), light weight (dry as well as wet), rock plate or some kind of protection ( i like to freewheel downhill) and good grip ( as minimal as i need in lug height to make the day). Well as i go pretty much XC with no trails i guess some protection for toes and wear from bushes wouldn’t be bad either..
I would really appreciate to have your own point of view with all your experience to pick 3-5 pair of shoes to choose from! And maybe i get 2 pairs in the end.. :-)
Best regards Marcus
Hi Marcus,
Well you are talking about my favorite shoe category and one that no one has really nailed yet. I just finished my mountain shoe post and it should published soon so you can refer to that when I mention a few shoes from it.
Of shoes that are out, my best recommendations that you haven’t tried are:
1. inov-8 Mudlcaw 300 (newer red/blue version): it’s one of the best fitting mountain shoes I’ve ever tried and more versatile traction than the X-Talon. Downside is no rock plate and lugs are pretty aggressive so I use them mostly for off trail outings.
2. adidas terrex boost: best overall midsole and outsole package out there with great rock plate and ride (Boost midsole is fantastic). Great all around outsole and grip too. Downside is the upper isn’t as comfortable as I’d like…upcoming terrex Agravic (which is in upcoming preview post) is going to address most of the upper issues and offer similar ride in lighter package. Agravic is shoe I’m most exited for that is coming out soon.
3. Dynafit Feline SL (see review here: link to runblogger.com): Like an X-talon 212 in feel but more versatile and slightly more protection; downside is no rockplate and while the last shape is awesome, the upper has a fair bit of stitching…the upcoming Feline Vertical looks awesome though and should address all of these shortcomings.
4. adizero XT Boost: you’ve read the review and while it isn’t an all out mountain shoe, it has one of the best rides I’ve tried and super versatile on routes/races that have a mix of faster running and steep/technical sections. No rockplate and 10mm drop are small drawbacks but don’t ruin the shoe at all for me.
5. Salming T1 – probably one of the most versatile trail/mountain shoes I’ve ever run in. It handles off trail pretty good and still runs good on pavement (not many shoes you can say that about). Super durable upper and great midsole ride. 5mm drop and no rock plate, but it is protective enough without it. Review here: link to runblogger.com
6. North Face Ultra MT: great for drier conditions and super sticky rubber and rock plate make it a nice option. 8mm drop and upper isn’t perfect, but still one of the better options out there that I’ve tried.
Look to my mountain shoe preview post for the: adidas terrex Agravic, Dynafit Feline Vertical, Salewa Lite Train, and Scarpa Atom all of which fit what we are both looking for: great snug midfoot/heel fit, rock plate, full rubber outsole, light and 4-6mm drop. Some of the best looking options yet but I haven’t run in them so can’t put my full stamp of approval on them yet. If I was you, I’d wait till they are available (should be by late February) and try them with a few of the options I listed above that sound interesting. Happy running! -David
Thank you David, I really appreciate your effort!
I’ll wait for the review and the newcomers sounds really exciting!!
//Marcus
(Ps. what do you think about the new S lab Speed? Improved fellcross 3)
I haven’t run in the S-Lab Speed, just the Fellcross 3. I’ve seen it and basically I would guess it runs pretty similar. They didn’t change much other than some slight outsole tweaks. The Fellcross 3 is probalby my favorite Salomon, but yes like you mentioned, I’m not crazy about Salomon. I don’t prefer the speed laces and their choice to use compressed eva on most of their midsoles leave them with a pretty mediocre ride in my opinion and they are super expensive too. That said they do some quality work with their uppers, I just don’t love the ride.
They’ve just had a snug fit and pretty strong outside for the terrain I’m running but I wont mention S-n again :-) and yes they’re expensive..
The fact that you said about compressed eva makes me understand why they feel a little dead..
Been looking on the net for the newcomers you mentioned and do you know anything about the dry and wet weight of the Adidas terrex Agravic, Dynafit Feline Vertical, Salewa Lite Train?
The Agravic looks really interesting and as you like the midsole boost I think they’re gonna be the first hand choice.
Does Agravic and Lite Train have a rock plate?
I don’t know about wet weights but the listed weights are Agravic (311 g), Dynafit FV (250g), and Salewa LT (245 g) all this an more info will be in the forthcoming preview post and yes Agravic and Lite Train have rock plates…the Agravic’s is pretty robust and extends through the midfoot which will help with foot fatigue on longer runs. I don’t know much about the Lite Train at this point other than what I saw in August.
Ok and thanks!
I think it would be interesting (at least from my point of view) if you could put in wet weight in your tests. I saw a guy doing a swim-running race with the praised Kigera2 who was very disappointed as it were 72 grams heavier per shoe after the swimming..
Great help, Marcus
Look like a boot. Maybe it is for run in hard condition. As my country don’t get snow or winter maybe it is suitable for trail run.
I’m still new and not really familiar with the shoe.
Not a boot at all. That gaiter is very thin and offers no support or structure. It’s a fast running trail shoe that works well on a wide varied of terrain. One of my favorites from this year! -David
Your review has made me curious about these shoes. Can you tell me if you wear them in the same size as the normal Adidas Adios Boost? (I seized half up from the v1 to the v2, as Pete already suggested).
I wear the same size as both v1 adios and v2 adios. They probably fit closer to v2 so I would guess sizing a half size up would be best unless you want a really precise fit. They are a great shoe and one of my favorites from 2015. -David
Thanks David. I ordered them because of your review. You are right about sizing, the same size as Adios Boost V2 works for me. And I love them. They work well off road and even so on road. Thanks for the advise.
Thanks for following up and glad to hear you like them! -David