Altra Duo Review
If you're in the market for a reasonably light (8.4oz/240g) road shoe that's somewhat firm and fits a healthy human foot, then the Duo is a good option. The Duo is not without its flaws, the main one being a tendency to pick up small stones under the sole. The other issue is that the sole seems to wear faster than you might expect. This is not as bad as early versions of The One, where the sole used to abrade like it was made of milk chocolate, but it's a little more than I would like. I'm only at about 120 miles, and there's already slight signs of wear on the outsole. On a more positive note however, the Duo is shaped like a healthy human foot, so it won't induce bunions, nor require you to have bunions to fit correctly. The Duo even has a little bit more height in the toe box than many Altra shoes tend to have. It's a little firmer than I would like for this weight, but that does confer some degree of protection without much cushioning, a plus point if you like a firmer running shoe. Like all Altra shoes, it's close to zero drop, with nothing to interfere with your natural biomechanics. I'm rating the Duo as "Recommended." (I use The Science of Running Shoes as the basis of how I test running shoes and what you should look for in a running shoe.)
Below are some pictures of the Duo after it's picked up some small stones. The first 2 pictures are from a run along and asphalt Greenway, that has just a few patches of loose stones. The later pictures with the darker sole are after a 43-mile run along a gravel trail (the New River State Park in Virginia.) You can see the Duo was crammed full of small stones, so you're probably wondering why I wore the Duo on a gravel trail. Let me talk you through my reasoning. I didn't want to wear a thin road shoe, like my favorite Altra Solstice as it wouldn't provide enough of protection from the stones, but I didn't want to wear a full trail shoe like the Altra Timp as I didn't need that much protection, nor did I want that much weight. The Duo is firm enough to provide the protection I needed, and the raised patches provide good grip on the patches of mud and other slick surfaces. The Duo did accumulate stones very rapidly, but not enough to significantly increase the weight of the shoe or compromise the cushioning. (The stones added about 0.4oz in case you're wondering, like I was.) While I found I can cut open the toe box of a shoe and run on gravel surfaces without getting any stones into the holes, I do prefer leaving the toe box intact if I have the option. That really limits me to an Altra, or a tiny subset of other shoes that are designed to fit a healthy human foot. And I found the Duo to be quite comfortable for a 40+ mile run.
- . The Duo has reasonable, but not great cushioning for its weight. It feels a little firm rather than hard, but my perception while running is that it's a little firmer than the numbers would suggest. This is probably because the Duo has a number of raised rings or patches of cushioning, creating an eggshell effect. Because the pressure is concentrated on these raised areas, they tend to compress a little more than the rest of the midsole. This creates a slightly softer, and more cushioned sole than you'd get from a more traditional, flat sole. I never felt that there was any unevenness from these raised areas, and the camp and you owe is a smooth and neutral underfoot. I would prefer that issue waiting this much provided more cushioning, or weigh far less, but the problem is far from egregious. However, Altra's claim of "maximum cushion and minimal weight" is somewhat laughable. It's a very long way from either maximum cushioning or minimal weight, and Altra's claim that "the cushion-to-weight ratio on this shoe is hard to beat" seems disingenuous at best. Every Altra road shoe I've measured has a better cushion-to-weight ratio! (The good news is that at least they're aware of this ratio.)
- . The Duo is effectively zero drop (not all Altra shoes are zero drop, regardless of what they claim.)
- . The Duo uses just one density of foam and doesn't attempt to manipulate or interfere with your natural biomechanics.
- . While the Duo is moderately flexible and quite springy, though I doubt if there's any performance benefit to be had.
- . The outsole is the Duo's weak point. The raised areas are naturally prone to rapid wear, and the gaps between the raised areas are the worst stone magnet I've ever come across. And once they are full of tiny stones, the effective cushioning of the shoe is dramatically reduced. Even running on what I think of as a fairly clean asphalt surface, the camp and you owe manages to find a few stones to pick up. In the photos above, you can see the harder rubber outsole as its colored yellow, but even after just 100 miles or so, the wear was noticeable, and I'm typically pretty gentle on my shoes.
. Altra shoes are some of the few that attempt to actually fit the human foot. The Duo does a great job of fitting the outline of the human foot, and like some other Altra shoes there's a little headroom for your toes. In fact, there's enough headroom that I didn't feel the urge to cut open the toe box.
- . The upper is unpadded except for a tiny bit around the ankle opening. The upper is inflexible, which I prefer over stretchy uppers. For some reason, Altra claim the Duo is for "Hot Weather Endurance Racing," and while it's reasonably breathable, there's nothing particularly noteworthy.
- . The Duo has a traditional tongue that is has a tab to attach it to the laces. There's a bit of padding down the middle of the tongue, which might help a little bit with the pressure on the top of the foot.
- Altra Solstice, an otherwise superior shoe. . The thin flat laces never came untied, something that surprised me a little given the problems I've had with the
- . The Duo has no noticeable heel counter.
This review was made possible by readers like you buying products via my links. I buy all the products I review through normal retail channels, which allows me to create unbiased reviews free from the influence of reciprocity, or the need to keep vendors happy. It also ensures I don't get "reviewer specials" that are better than the retail versions.
2 Update After 210 Miles
I've come to quite enjoy running in the Duo, far more than I expected, and it's one of my preferred shoes for speed work.
- As is usual with running shoes, the Duo has softened a little over the miles as the foam becomes more compliant. I rather like this, but it's still a reasonably firm shoe. There's a hint of non-linearity in the cushioning I've noticed; the initial contact is relatively soft, and then as you land the cushioning firms up. Part of this is due to the "egg crate effect" of the sole and part due to the rather soft insole, but it seems to have become more noticeable over time.
- As you'd expect, the outsole has worn quite a bit as the contact patch is much smaller than you'd get on a shoe with a flat sole. I'm generally quite gentle on my shoes, and I've got quite a bit of wear on the outsole after just 210 miles.
- The more rapid wear on the outsole exacerbates the compression of the midsole foam, making the forefoot uneven and twisting the foot towards the midline slightly. At this mileage, the effect is not a problem, and I'd estimate the area under the ball of the foot is only 2-3mm lower. This is partly because the insole has only compressed a tiny fraction. Most insoles are as durable as milk chocolate on a hot day, so this is a noteworthy difference.
- The gaps in the outsole continue to be a magnet for small stones, and prying them out is quite tedious, requiring a tool such as a flat head screwdriver.
- You'll notice on the pictures that there's quite a bit of wear on the outside rear of the heel, which occurs on only a subset of shoes I run in. I don't generally heel-strike, and my current guess is that the heel is scraping slightly before landing. The Duo doesn't grip my heel in the way most shoes do, so it's possible it's dropping away from my foot slightly.
- The Duo has fairly good grip on wet surfaces, especially if there's a little mud on the ground. This is much better than I've found in a flat soled shoe like the Altra Solstice.
3 A Comparison with other Recommended Shoes
If you're looking for "the best of the best" running shoe, here are my top picks. Of course, the answer will depend a little on what you're looking for, so I have recommendations for various categories.
For a more detailed on running shoes see the Recommendations for Best Running Shoes. This table lists the key attributes of What to Look for in Running Shoes. For more detailed information, on the shoes see detailed shoe comparison.
|Saucony Type A Review||Saucony||A/A7||Recommended||$100||6.0||6.7||12.1||19||22||1||4.1||7|
|Saucony Type A6 Review||Saucony||A6||Highly Recommended||$100||7.7||6.1||9.5||17||21||4||4.7||7|
|Saucony Type A8 Review||Saucony||A8||Highly Recommended||$90||7.1||6.2||9.7||19||20||-1||4.4||7|
|Adidas Adios Boost 2 Review||Adidas||Adios||Worth considering||$140||4.4||8.6||13.4||17||27||11||3.8||6|
|Hoka Bondi 5 Review||Hoka||Bondi||Recommended||$150||5.7||11.6||18.1||38||42||5||6.7||2|
|Hoka Clayton 2 Review||Hoka||Clayton2||Highly Recommended||$150||8.6||8.3||12.9||23||28||1||7.1||5|
|Hoka Clifton 4 Review||Hoka||Clifton4||Worth considering||$130||7.2||9.3||14.5||30||35||10||6.7||3|
|ON Cloudflash Review||On Cloud||Cloudflash||Worth considering||$180||4.2||8.3||14.6||19||26||7||3.5||6|
|On Cloudracer Review||On Cloud||Cloudracer||Worth considering||$130||5.4||8.2||12.8||19||27||5||4.4||7|
|ON Cloud X Review||On Cloud||CloudX||Not recommended||$140||4.3||8.3||16.3||21||27||7||3.6||7|
|Mizuno Wave Cruise Review||Mizuno||Cruise||Worth considering||$120||6.3||5.9||12.5||17||20||7||3.7||6|
|Newton Distance IV Review||Newton||Distance||Worth considering||$155||7.1||9.1||14.2||26||31||3||6.4||5|
|Asics Gel DS Racer 10 Review||Asics||DS Racer||Worth considering||$110||7.8||7.0||10.9||21||26||6||5.4||5|
|Altra Duo Review||Altra||Duo||Recommended||$130||5.6||8.4||13.1||29||29||1||4.7||5|
|Mizuno Wave Ekiden 8 Review||Mizuno||Ekiden||Worth considering||$115||5.3||5.7||14.6||13||18||6||3.0||8|
|Saucony Endorphin 2 Review||Saucony||Endorphin 2||Worth considering||$115||7.5||5.1||9.6||15||13||-1||3.8||8|
|Adidas Energy Boost Review||Adidas||Energy||Worth considering||$160||6.8||10.0||15.6||20||30||7||6.8||5|
|Altra Escalante Review||Altra||Escalante||Best of the Best||$130||8.6||8.7||13.5||28||25||-1||7.5||6|
|Saucony Fastwitch Review||Saucony||Fastwitch||Highly Recommended||$90||9.0||7.1||11.1||20||22||4||6.4||7|
|Topo Fli-Lyte 2 Review||Topo||Fli-Lyte2||Highly Recommended||$100||6.4||9.1||14.2||24||26||3||5.8||5|
|Reebok Floatride Run Review||Reebok||Floatride||Worth considering||$150||7.2||9.6||14.9||28||34||10||7.0||5|
|Saucony Freedom Review||Saucony||Freedom||Recommended||$160||5.1||10.7||16.6||25||29||3||5.4||6|
|Skechers GORun 4 Review||Skechers||GORun||Not recommended||$100||5.7||7.5||11.7||15||23||3||4.3||7|
|Skechers GOrun Ultra 2 Review||Skechers||GRU||Worth considering||$90||7.1||10.0||15.6||28||34||8||7.1||4|
|Asics GT 2000 Review||Asics||GT 2000||Not recommended||$120||4.5||11.2||17.4||28||35||5||5.1||2|
|New Balance Hanzo S Review||New Balance||Hanzo||Worth considering||$110||7.1||6.9||10.7||21||19||2||4.9||5|
|Hoka Hupana Review||Hoka||Hupana||Recommended||$115||5.7||8.9||13.9||31||36||7||5.1||4|
|Asics Gel Hyper Speed 7 Review||Asics||Hyper Speed||Highly Recommended||$75||10.2||6.3||9.8||22||26||5||6.4||6|
|Altra Instinct 4.0 Review||Altra||Instinct 4.0||Worth considering||$120||5.7||9.8||15.3||29||25||-1||5.6||5|
|Asics Tarther Kainos 3 Review||Asics||Kainos||Worth considering||$130||9.4||6.9||10.7||17||27||9||6.4||6|
|Altra King MT||Altra||King MT||Recommended||$140||4.1||10.7||20.8||19||21||-1||4.4||5|
|Saucony Kinvara 8 Review||Saucony||Kinvara 8||Best of the Best||$110||8.8||8.6||13.4||26||31||3||7.5||5|
|Altra Lone Peak||Altra||Lone Peak||Highly Recommended||$120||4.9||11.4||17.7||23||25||-2||5.6||4|
|Nike Zoom Streak LT 3 Review||Nike||LT3||Best of the Best||$80||8.3||5.4||8.4||16||21||4||4.5||5|
|Nike Zoom Streak LT 4 Review||Nike||LT4||Recommended||$90||9.2||5.5||8.5||15||21||5||5.0||7|
|Nike LunarSpider R5 Review||Nike||LunarSpider||Recommended||$125||6.5||6.7||10.4||17||21||3||4.3||6|
|Hoka Mafate Speed Review||Hoka||Mafate||Highly Recommended||$170||7.1||11.9||18.5||39||40||4||8.5||1|
|Pearl Izumi EM Road N0 v2 Review||Pearl||N0||Highly Recommended||$100||7.5||6.5||10.1||14||20||4||4.9||8|
|Saucony Nomad Review||Saucony||Nomad||Worth considering||$110||4.1||10.5||17.2||25||27||2||4.3||4|
|Hoka Odyssey Review||Hoka||Odyssey||Highly Recommended||$130||8.0||9.4||14.6||37||45||5||7.5||3|
|Altra Olympus 2.5 Review||Altra||Olympus||Highly Recommended||$150||6.9||11.8||18.4||34||34||2||8.2||3|
|Altra One 3.0 Review||Altra||One||Recommended||$100||5.8||8.8||13.7||23||23||0||5.1||6|
|Asics Piranha SP 5 Review||Asics||Piranha||Recommended||$100||9.5||4.2||6.5||11||15||3||4.0||9|
|Brooks PureFlow 5 Review||Brooks||PureFlow||Worth considering||$110||5.7||9.7||15.1||26||29||5||5.5||8|
|Salming Race Review||Salming||Race||Worth considering||$130||6.5||6.5||10.1||16||19||4||4.2||6|
|New Balance RC1600 v2 Review||New Balance||RC1600||Highly Recommended||$110||8.3||5.6||8.7||15||21||5||4.6||8|
|New Balance RC5000v2 Review||New Balance||RC5000v2||Best of the Best||$125||13.4||4.0||6.2||13||21||6||5.4||7|
|Skechers GoRun Ride 3 Review||Skechers||Ride||Worth considering||$85||5.6||8.5||13.2||18||28||6||4.7||8|
|Nike RN Distance 2 Review||Nike||RNDist2||Worth considering||$120||7.6||9.2||14.3||25||28||4||7.0||7|
|Inov-8 RoadXTreme 220 Review||Inov-8||RXT-220||Worth considering||$120||4.9||8.0||18.2||14||17||3||3.9||8|
|Salomon Sense Ride Review||Salomon||Sense||Worth considering||$120||8.0||10.0||15.6||24||29||3||8.0||4|
|Altra Solstice Review||Altra||Solstice||Highly Recommended||$90||6.6||8.1||12.5||23||25||1||5.3||6|
|Topo ST-2 Review||Topo||ST-2||Highly Recommended||$90||7.7||7.3||11.4||20||18||0||5.7||7|
|Hoka Stinson Lite Review||Hoka||Stinson||Highly Recommended||$160||6.9||11.6||18.1||35||40||6||8.0||0|
|Altra Superior||Altra||Superior||Highly Recommended||$110||5.4||9.9||15.5||23||25||0||5.4||5|
|Adidas Takumi Sen 3 Review||Adidas||Takumi Sen 3||Highly Recommended||$160||7.3||6.6||10.2||17||21||4||4.8||5|
|Altra Timp Review||Altra||Timp||Best of the Best||$130||5.4||11.6||18.1||28||31||2||6.2||3|
|Altra Torin 2.0 Review||Altra||Torin||Worth considering||$125||5.4||9.6||14.9||28||25||-1||5.2||4|
|Hoka Tracer Review||Hoka||Tracer||Recommended||$130||6.8||7.4||11.5||21||24||2||5.0||5|
|Merrell Trail Glove 4 Review||Merrell||Trail Glove 4||Best of the Best||$100||3.2||8.4||23.8||13||13||0||2.7||10|
|Topo Tribute Review||Topo||Tribute||Recommended||$100||5.6||7.3||11.4||20||18||-1||4.1||6|
|Mizuno Wave Universe 5 Review||Mizuno||Universe||Highly Recommended||$125||10.1||3.1||10.6||9||12||1||3.1||9|
|Altra Vanish-R Review||Altra||Vanish-R||Recommended||$100||9.7||5.3||8.2||19||21||0||5.1||8|
|Merrell Vapor Glove 3 Review||Merrell||Vapor Glove 3||Highly Recommended||$85||2.0||6.1||27.6||6||5||0||1.2||10|
|Nike Vaporfly 4% Review||Nike||Vaporfly||Best of the Best||$250||9.8||7.2||11.2||25||37||8||7.1||2|
|New Balance Vazee Pace Review||New Balance||Vazee Pace||Worth considering||$110||5.6||8.6||13.4||18||24||6||4.9||5|
|Asics TartherZeal 3 Review||Asics||Zeal||Worth considering||$140||10.3||6.3||9.8||17||27||9||6.4||6|
|Saucony Zealot 3 Review||Saucony||Zealot3||Recommended||$130||8.4||9.5||14.8||29||32||4||8.0||6|
|Nike Zoom Fly Review||Nike||Zoom Fly||Worth considering||$150||7.8||8.7||0.0||29||36||8||6.8||3|
It's not a running shoe, but I love the Hoka Tor Ultra hiking boot and I've tested the Altra Lone Peak Boot, the Hoka Tor Speed 2, and the Inov-8 Roclite 325 hiking boots
Older shoe reviews: Saucony Hattori Review, Mizuno Cursoris Review, Skechers GO Bionic 2 Review, Hoka Clifton Review, Saucony Virrata 2 Review, Brooks PureCadence 3 Review, Brooks PureConnect 3 Review, Brooks PureFlow 3 Review, Skechers GO Bionic 2 Review, New Balance 980 Review, Brooks Transcend 2 Review, Hoka Huaka Review, Patagonia EVERlong Review, Asics 33-DFA Review, Hoka Conquest Review, Saucony Cortana Review, Puma Faas 100 R Review, Saucony Fastwitch Review, Nike Free Review, Asics Gel Lyte 33 Review, Skechers GOmeb Speed Review, Skechers GOrun Ultra Road Review, Nike LunaRacer Review, Altra Paradigm Review.