Our verdict

With its distinct lack of medial posts or a rigid shank and ridiculously cushy midsole, we're hard-pressed to describe the Nike Structure 25 as a stability shoe. However, the way its smooth and supportive ride that subtly nudges us toward a more neutral stride is undeniable. This workhorse of a daily trainer may not be the fastest, but we found that it's comfortable and responsive enough for easier paces whether we were out for a recovery run or steadily crushing mile markers on longer hauls. Also, the shoe's warm upper and consistent performance in our freezer tests means that it's not just a fair-weather friend but an excellent year-round companion.

Pros

  • Stable and supportive ride
  • Plush and protective cushioning
  • Comfy and flexible underfoot
  • Consistent in the cold
  • Good for long slow distance runs
  • No break-in required
  • Warm and roomy toebox
  • Durable, high-quality upper
  • Lots of colorway options

Cons

  • Quite heavy
  • Average breathability at best
  • Clunky at high paces

Audience verdict

85
Good!
  • Top 20% most popular running shoes

Who should buy

We recommend the Nike Structure 25 as an excellent choice for: 

  • Overpronating runners who want a comfy yet stable daily trainer that rides like a neutral shoe
  • Heel strikers in the market for a responsive and well-cushioned road shoe that's versatile enough to tackle recovery runs as well as long-distance efforts.
  • Broad-footed runners who need a toebox with some added internal real estate
  • Runners in colder climates looking for a warm shoe that performs consistently no matter how low temperatures drop

Nike Structure 25 buy

Who should NOT buy

While stated to have a 10 mm heel drop, we found the Structure 25 to have an even steeper offset of 12.1 mm. While this is conducive for heel strikers and those with lower leg issues, we recommend that those with a forefoot striking stride go for a shoe with a lower drop like like the Hoka Arahi 6

The Structure 25's toebox may prove to be a little too roomy for those with narrow feet. We recommend either sizing down slightly for a more snug fit or looking at a less spacious alternative like the ASICS Gel Kayano 30

Nike Structure 25 cut

While its Cushlon 3.0 midsole feels quite responsive underfoot, we found that the Structure 25 lacks the energy return and is a little too heavy to facilitate speedier runs. The Saucony Tempus feels snappier underfoot and is better suited for high-paced sessions. 

Although the Structure 25 does boast a fair amount of airflow, its generous padding and dense upper mesh mean that it feels quite toasty on warmer days. For a more breezy alternative that doesn't turn into a sweatbox as the mercury rises, we recommend checking out the Brooks Adrenaline GTS 23 instead. 

Breathability

To test the breathability of the shoe, we pumped the Structure 25 full of smoke to see how easily it vents through the upper. As the footage demonstrates, it takes quite a long while before any smoke is able to filter out of the shoe. Eventually, a light haze emerges and flows steadily, albeit in rather thin wisps, throughout the shoe. This leads us to give the Structure a middle-of-the-road score of 3 out of 5 for breathability. This is, no doubt, thanks in part to the generous amount of thick padding throughout the shoe which does feel quite warm as we take the shoe for test runs. 

The Saucony Triumph 20, on the other hand, blew out billows of smoke that earns it a perfect score in this test. 

However, how easily the light shines through a backlit cross-section of the shoe's upper over a backlight would lead us to believe otherwise as we've found that this is usually an indicator of good breathability. 

Our microscope lays our questions to rest as it reveals how densely woven the Structure 25's multi-layered upper mesh is. We only see very small visible gaps in between the braids that go all the way through and promote some level of airflow. This explains the smoke's delayed ability to start filtering out of the shoe in our first assessment. 

Nike Structure 25 Breathability

Nike Structure 25 Breathability 6
Test results
Structure 25 3
Average 3.8
Compared to 234 running shoes
Number of shoes
1
Breathability
5

Durability

Toebox durability

To simulate extreme wear and tear, we fired up our Dremel to 5K RPM and set it against the Structure 25's toebox with 3.2N of force. 

After four seconds of grinding, we found that our tool had an insignificant effect on the shoe's mesh as the damage left behind is barely noticeable. This stellar performance leads us to give the Structure 25 a toebox durability of 5 out of 5. 

Nike Structure 25 Toebox durability 2

Compare that to the abysmal performance of the ASICS Gel Pulse 13 which had its toebox obliterated in this same test. 

Test results
Structure 25 5
Average 2.4
Compared to 168 running shoes
Number of shoes
1
Toebox durability
5

Heel padding durability

The heel collar proved to be almost as hardy as the toebox in its face off against our Dremel. 

While our tool was able to menace the lining to a certain extent, it wasn't able to pierce through it and reach the soft padding within. As such, we give the Structure 25 a heel padding durability score of 4 out of 5. This is excellent for a daily trainer and means that no amount of heel rubbing, even when going sockless, will significantly compromise the shoe's comfort or lockdown at the rearfoot. 

Nike Structure 25 Heel padding durability
Test results
Structure 25 4
Average 3.2
Compared to 164 running shoes
Number of shoes
1
Heel padding durability
5

Outsole hardness

Pressing our durometer against the Structure 25's outsole yields a reading of 88.5 HC. This is quite a bit harder than our current lab average which bodes well regarding the outsole's longevity.  

Nike Structure 25 Outsole hardness
Test results
Structure 25 88.5 HC
Average 80.5 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 285 running shoes
Number of shoes
52.1 HC
Outsole hardness
93.0 HC

Outsole durability

Now spinning at 10K RPM, we set our Dremel against the outsole for a grand total of twenty-two seconds of abrasive force. 

Afterward, we used a tire tread gauge to measure the indentation left behind in the wake of the test and found that 0.8 mm of rubber had been worn away. This isn't quite as durable as we had anticipated based on the hardness of the rubber but still puts the Structure 25 on par with our current lab average. We therefore expect this shoe to last the expected shelf life of 400 to 500 miles before any significant signs of wear and tear appear. 

Nike Structure 25 Outsole durability 2
Test results
Structure 25 0.8 mm
Average 0.9 mm
Compared to 146 running shoes
Number of shoes
0.0 mm
Outsole wear
2.0 mm

Outsole thickness

The Structure 25's outsole isn't as robust as our current lab average at only 2.3 mm thick according to our caliper measurements.

Nike Structure 25 Outsole thickness

This, along with the decision to go for incomplete coverage of the midsole, is surely a decision made with shedding weight off the shoe. 

Nike Structure 25 Outsole thickness 2
Test results
Structure 25 2.3 mm
Average 3.2 mm
Compared to 304 running shoes
Number of shoes
0.0 mm
Outsole thickness
6.6 mm

Weight

In spite of the aforementioned weight-saving measure, the Structure 25 still tips our scale at a heavier-than-average 10.7 oz (302g). However, this is still on par with the average stability shoes and doesn't feel overly burdensome underfoot, especially when it comes to easier paces. 

Nike Structure 25 Weight
Test results
Structure 25 10.65 oz (302g)
Average 9.38 oz (266g)
Compared to 305 running shoes
Number of shoes
5.26 oz (149g)
Weight
12.56 oz (356g)

Cushioning

Heel stack

Using our caliper, we measured the Structure 25's stack to be 36.7 mm thick at the heel which makes the 37 mm stated by Nike quite accurate. We like to see that here in the lab. 

Nike Structure 25 Heel stack 5

Having this amount of foam underfoot isn't just good for heel strikers, but is suitable in general for long distances where most runners tend to revert to heel landings as fatigue sets in. Furthermore, it really allows us to sink into and savor Nike's Cushlon 3.0 midsole foam during our test runs. 

Test results
Structure 25 36.7 mm
Average 33.7 mm
Compared to 304 running shoes
Number of shoes
7.6 mm
Heel stack
45.7 mm

Forefoot stack

Nike wasn't as accurate with their forefoot stack measurement of 27 mm as we found that there is actually only 24.6 mm of foam in that part of the midsole according to our caliper. 

Nike Structure 25 Forefoot stack

This is still an average amount of foam at the forefoot for a road shoe and means that we enjoyed comfy forefoot landings as well while testing this shoe. 

Test results
Structure 25 24.6 mm
Average 25.0 mm
Compared to 304 running shoes
Number of shoes
7.6 mm
Forefoot stack
36.9 mm

Drop

The discrepancy with the forefoot measurement means that the Structure 25 has a heel drop of 12.1 mm as opposed to the 10 mm as stated by Nike. This isn't totally out of the norm for us here in the lab as we've come across many similar deviations while testing shoes as explored in this article. Nevertheless, this still puts the Structure 25 in the category of high-drop shoes that tend to favor runners with a heel-striking stride or those with calf or lower leg issues as it puts more load on our hips and knees.

Nike Structure 25 Drop

While we believe that midfoot strikers should still get some benefit out of this shoe, this steep offset means that forefoot strikers won't be able to appreciate all the Structure 25 has to offer. For those runners, we recommend going for a shoe with a lower drop like the Saucony Tempus (8.5 mm) or the Hoka Arahi 6 (4.1 mm) instead. 

Test results
Structure 25 12.1 mm
Average 8.7 mm
Compared to 304 running shoes
Number of shoes
-0.8 mm
Drop
16.1 mm

Insole thickness

At 5 mm thick according to our caliper measurements, the Structure 25's insole is ever so slightly thicker than our current lab average. This gives us a nice and soft footbed to land in before the midsole cushioning even kicks in. 

Nike Structure 25 Insole thickness
Test results
Structure 25 5.0 mm
Average 4.5 mm
Compared to 300 running shoes
Number of shoes
1.5 mm
Insole thickness
7.3 mm

Midsole softness

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.

One thing we love about the Structure 25 is its comfy yet supportive ride that doesn't feel like your typical stability shoe. It pampers our feet in the right ways while subtly guiding us towards a more neutral stride. What's more, it feels great out of the box but ages like a fine wine and feels even better after a few runs. 

Pressing our durometer against the Cushlon 3.0 midsole gives us quite a plush reading of 17 HA.  When combined with the shoe's robust stack, this explains the soft and pillowy landings we enjoyed while testing the Structure 25.

Nike Structure 25 Midsole softness

However, the Air Zoom unit embedded in the forefoot means that the midsole doesn't feel as cushy in this part of the shoe, with the trade-off being a little extra pep to our toe-offs. It's not crazy springy but it was a welcome amount of energy return during our longer runs. 

Test results
Structure 25 17.0 HA
Average 21.4 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 232 running shoes
Number of shoes
8.5 HA
Midsole softness (soft to firm)
41.5 HA

Difference in midsole softness in cold

We placed the Structure 25 in our freezer to observe the effects of cold conditions on the midsole. 

Nike Structure 25 Difference in midsole softness in cold

After twenty minutes of chilling, we pressed our durometer against the Cushlon 3.0 once more and found that it only got 17.6% firmer. This is quite consistent compared to our current lab average and, with a post-freezer reading of 20 HA, the Structure 25 should still feel comfy and forgiving underfoot no matter how cold it gets. 

Test results
Structure 25 17.6%
Average 25.5%
Compared to 231 running shoes
Number of shoes
0%
Difference in midsole softness in cold
100%

Stability

Lateral stability test

Incredibly for a shoe that doesn't use any rigid medial posts or shanks in its construction, the Structure 25 manages to feel incredibly stable underfoot as it gently nudges us towards a more neutral gait. We'll explore the factors that play into this steady ride over the next few tests. 

Torsional rigidity

We found the Structure 25 to be quite difficult to bend and twist manually, leading us to give it a subjective torsional rigidity score of 4 out of 5. As such, the shoe is able to maintain a nice and level landing surface by resisting any excessive lateral movements of our foot. 

Test results
Structure 25 4
Average 3.2
Compared to 283 running shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

The heel counter is also quite stiff, earning another score of 4 out of 5 in our manual assessment.

This strong structure in combination with the generous amount of padding back there presents a good balance of stability and comfort as it locks our rearfoot in place and mitigates rolling without putting too much on our heels or tendons. 

Test results
Structure 25 4
Average 2.8
Compared to 267 running shoes
Number of shoes
1
Heel counter stiffness
5

Midsole width in the forefoot

Another big factor in the Structure 25's well-balanced ride is its broad base. Using our caliper, we measured its midsole to be 116.4 mm wide at the forefoot which is quite a bit wider than average. 

Nike Structure 25 Midsole width in the forefoot
Test results
Structure 25 116.4 mm
Average 113.7 mm
Compared to 305 running shoes
Number of shoes
100.5 mm
Midsole width in the forefoot
126.5 mm

Midsole width in the heel

At 95.3 mm wide according to our caliper measurements, the midsole is even wider at the heel when compared to our lab average. This gives heel strikers a robust landing platform that will surely keep them feeling surefooted with every stride. 

Nike Structure 25 Midsole width in the heel
Test results
Structure 25 95.3 mm
Average 90.5 mm
Compared to 305 running shoes
Number of shoes
74.9 mm
Midsole width in the heel
106.6 mm

Flexibility

Stiffness

Despite its relatively high level of torsional rigidity, we discovered that the Structure 25 is quite pliable in a longitudinal sense. After securing it to our workbench by the forefoot, we used a force gauge to bend the shoe and found that 22.1N of force is required to get it to 90 degrees. 

This result makes the Structure 25 more flexible than the average road shoe and means that it's able to conform to the flexion of our foot with relative ease. 

Nike Structure 25 Stiffness 2
Test results
Structure 25 22.1N
Average 29.2N
We use an average of four tests. The video shows one of those tests.
Compared to 287 running shoes
Number of shoes
2.2N
Stiffness
94.4N

Difference in stiffness in cold

We also repeated our flex test after leaving the shoe in the freezer for twenty minutes and found that it only became 16.7% stiffer when exposed to the cold. This not only makes the Structure 25 much more consistent than the average shoe under similar conditions but, with only 25.8N of force needed to bend the shoe to the desired point, it's more flexible than most shoes at room temperature! Taking this into consideration along with the midsole's post-freezer performance and the shoe's toasty upper, we conclude that the Structure 25 will make a great year-round companion no matter how frosty it gets in the winter. 

Test results
Structure 25 16.7%
Average 35.9%
Compared to 287 running shoes
Number of shoes
0%
Difference in stiffness in cold
148%

Grip / Traction

We had no complaints with the outsole grip while testing the Structure 25 over the normal surface we expect to come across when road running. Even a smattering of rain that left the asphalt wet was no cause for hesitation during our runs in this shoe. 

Nike Structure 25 grip

Size and fit

Toebox width at the widest part

The Structure 25 boasts a roomy toebox that we measured to be 100.4 mm wide at its widest point. This makes it broader than our current lab average which means that it should provide an accommodating fit for most runners, even those with broad feet. 

Nike Structure 25 Toebox width at the widest part

On the other hand, runners with narrow feet may find that they have a little too much room in the forefoot to achieve a secure lockdown. However, since we found the Structure 25 to be a little long for a men's US size 9 compared to our lab average, we suggest that those runners try sizing down for a better fit. Alternatively, the ASICS Gel Kayano 30 comes with a more snug toebox that won't feel so spacious. 

Test results
Structure 25 100.4 mm
Average 98.4 mm
Compared to 305 running shoes
Number of shoes
89.5 mm
Toebox width at the widest part
109.1 mm

Toebox width at the big toe

Moving up to the area around the big toe, the Structure 25's toebox is 77.4 mm wide according to our caliper. This is on par with our current lab average and means that we had plenty of room to splay out comfortably during our test runs. However, those with certain foot shapes or very broad feet should look into the shoe's extra wide option to avoid developing hotspots or blisters. 

Test results
Structure 25 77.4 mm
Average 78.2 mm
Compared to 179 running shoes
Number of shoes
60.4 mm
Toebox width at the big toe
92.5 mm

Tongue: gusset type

Despite being non-gusseted, we didn't experience any issues with the tongue slipping from side to side as we tested the Structure 25.

Nike Structure 25 Tongue: gusset type open

This is thanks to its chunky nature and the long central lace loop that helps mitigate slippage.

Nike Structure 25 Tongue: gusset type lace loop
Test results
Structure 25 None

Comfort

Tongue padding

At 11.8 mm thick according to our caliper measurements, the Structure 25's tongue is much beefier than our current lab average. As such, we experienced an incredibly luxurious lockdown once we were laced up and ready to go, with the laces themselves sinking into the pillowy tongue and virtually disappearing from our consciousness. 

Nike Structure 25 Tongue padding
Test results
Structure 25 11.8 mm
Average 5.6 mm
Compared to 302 running shoes
Number of shoes
0.5 mm
Tongue padding
14.2 mm

Removable insole

The Structure 25's insole is easily removed so it can easily be replaced with an after-market alternative or a custom orthotic for added arch support if necessary. 

Nike Structure 25 Removable insole
Test results
Structure 25 Yes

Misc

Reflective elements

The Structure 25 features a small reflective streak at the heel that provides some, albeit minimal, nighttime visibility. We still recommend using additional high-vis gear whenever taking this shoe out for a nocturnal romp. 

Test results
Structure 25 Yes