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Nike ZoomX Invincible Run Flyknit 3: Very Different
By Andrea Myers and Nathan Brown

The Nike Invincible Run series is one of a few shoes that uses a brand's top-shelf foam utilized for racing in a training shoe. ZoomX became well-known in the original Vaporfly and has been incorporated into every new racing model since. The Invincible Run is a different take on ZoomX, making it a suitable platform for easy runs and high-mileage training. We will dive into what it takes to stabilize a foam like ZoomX to make it runnable as well as the changes in this newest version.

Price: $179.95 at Running Warehouse
Weight: 10.6oz, 300g (men's size 9), 9.1oz, 258g  (women's size 8)
Stack Height: 40mm/31mm
Drop: 9mm
Classification: Max cushion trainer


The Invincible Run 3 is Nike's premier training shoe, featuring a whole lot of ZoomX in the midsole. The shoe sits on a platform that is very wide in the heel and forefoot with significant sole flaring but has some nice beveling throughout the shoe to help with a smooth landing regardless of where you first contact the ground. Upper security overall is an issue, which poses some issues for certain types of runs. This is best for long runs, easy runs, and as a mileage workhorse.

I really enjoyed testing the Invincible Run 2 last year thanks to its bouncy ZoomX midsole, geometry that seemed well-tuned for midfoot striking, and comfortable fit. I was really interested in testing v3 because I knew Nike had made some changes to the geometry and the upper, and I wanted to see how it compared to v2. The most notable differences in v3 for me are a much firmer midfoot landing and push off, a more breathable Flyknit upper, and difficulty achieving sufficient lace lockdown. I personally prefer the fit and ride of v2, but some runners (particularly heel strikers) may do better in this version. As a max cushioned daily trainer, the Nike ZoomX Invincible Run Flyknit 3 is a nice easy day shoe that provides plenty of protection from the pavement.

: New Balance SC Trainer, ASICS Nimbus 25
PAST MODEL: Nike Invincible 2


Nathan: Fit is the main downfall of the Invincible Run 3 despite overall a true-to-size fit in length and width. Before getting into the issues, let's look at the construction. The heel is a semi-rigid heel counter that is of moderate width and has mild padding. The Flyknit upper has minimal stretch, and the toe box has a lower vamp (height). It has decent width but feels a bit low on the foot at least over the first number of miles. I have over 50 miles on my pair and the upper has stretched a bit to give nice space in the toe box. So what are the issues? For some, it will be the lower volume. But the main issue is in the heel. I had a hard time achieving a secure lockdown. This may be due to the moderate width of the heel counter and also the lacing. There is no gusset in the tongue and the top row of laces is a bit lower on the foot (towards the midfoot). That leads to a bigger "throat" of the shoe and I couldn't get it secure. To be honest, this didn't bother me for easy runs, but for long runs (I have a 1.5 and 2-hour run in them). However, I did a number of different mild-tempo runs and a long-run workout, and the lack of security really hindered performance. 

Andrea: The Nike ZoomX Invincible Run Flyknit 3 fits true to size in my usual women's 9.5, although it does fit shorter than v2. It has sufficient room in the toe box and I did not experience any discomfort at my 1st or 5th MTPs. The midfoot is normal width, but the rearfoot fits wide and loose, which caused issues achieving sufficient lockdown. No matter how I laced the shoes, including using a heel lock, I could not keep my heel from slipping in these shoes. It also felt like the laces loosened up as I ran, so even if I started out my run with the heel feeling secure, after less than a mile it would loosen up, causing me to stop and adjust the laces. I did not experience any heel slippage in v2, and in comparing the two shoes, v3 is not only wider at the heel, but the laces do not come up as far on the ankle and there is less heel collar padding. These three factors combine to result in much less heel security in v3.

The tongue is thick, padded, and non-gusseted. There is a lace loop on the tongue that helps to hold it in place and I did not experience any tongue slipping while running. The laces are thin and do not stretch. The well-padded tongue adequately protects the dorsum of the ankle from lace bite, but the laces tie further down the foot as compared to v2, leading to a feeling of the tie being closer to the midfoot than the ankle.

There is a fairly rigid heel counter at the lower half of the heel, which wraps around the heel medially and laterally. The upper half of the heel counter is more flexible, but still has some structure. The heel collar has some padding, but less than v2 and it does not extend as far forward. As I mentioned above, heel security in v3 is lacking, which limits the utility of the shoe for me. I could use it for shorter, very easy runs, but picking up the pace at all just resulting is more heel insecurity.


 The Invincible 3 is a premium high-mileage workhorse trainer. The outsole rubber is durable, there is a lot of foam underfoot, and the upper (despite its issues) is built to last. The midsole is full ZoomX, but it has a different feel than the ZoomX experience in the Vaporfly. I don't know if this is because it is a different "formula" of Zoom X or because of the geometric design, but it feels less bouncy and more controlled and firm, particularly in the forefoot. Don't get me wrong, there is still a good amount of compliance (compression) of the foam, particularly in the heel, and overall is a soft shoe without being mushy. But compared to other uses of ZoomX, it feels firmer.

I have taken this shoe on a 10-mile workout that included three periods of 2 miles at my half-marathon pace. My experience on this run was overall positive. The rebound from the ZoomX and slightly stiff forefoot rocker made it perform well despite the 10.6oz weight. What hindered it most was the lack of security in the heel, as it felt like I lost efficiency trying to pull the heel along. I also did an easy 2-hour run with some marathon effort pace and that was probably my favorite run in these shoes. Finally, I did a myriad of easy runs (felt really good) and then one fartlek, which I wouldn't do again. As I dipped below half marathon pace, I could feel the weight and things started getting clunky. Ultimately I find this shoe best for long runs, easy runs, and daily mileage, but also has enough bounce and rigidity from the full-length rubber outsole that it did well picking up the pace a bit.

The performance of v3 was much different than v2 for me. After every run, as I walked up my driveway, I noticed that the shoe felt significantly bouncier walking than running. The most obvious reason for this is that while I midfoot strike when running, I heel strike when walking. It feels like this shoe was designed for heel striking (which the vast majority of runners do). While walking, I could feel the familiar ZoomX bounce at the heel, which pushed me into a firmer midfoot and forefoot for push off. When running and landing at the lateral midfoot, the shoe feels firm, dense, and a little heavy. With 31mm of stack in the forefoot, there is still plenty of foam under the forefoot, and I definitely felt more than sufficiently protected from the road, but it was not at all like the midfoot bounce that I loved in v2. While v2 felt like a lower drop shoe thanks to the severe sole flare in the heel and heel bevel, v3 feels like a 9mm drop shoe. Like other higher-drop shoes, I felt like the heel got in the way at initial contact. This is likely due to the heel bevel being smaller in v3 as compared to v2. The forefoot is quite rigid, in large part to the full-length rubber outsole. The stiff outsole in combination with the forefoot rocker contribute to a smooth transition to push off.

At 10.6oz for a men's size 9 and 9.1oz for a women's size 8, this is not a lightweight shoe, but also nowhere near as heavy as the New Balance SC Trainer at 11.3oz/10.5oz (which happens to be my favorite recovery run shoe). While I notice the weight of the SC Trainer, I find it worth it for the protective and rockered ride. The weight and geometry of the Invincible 3 makes it feel a little clunky and heavy for my running style, even at easy paces. This shoe will be an easy day shoe for most runners; some may be able to take it for long runs if it works with their mechanics.

The rubber outsole provides excellent traction, even on wet or sand covered roads. I would expect greater than average outsole durability because of its extensive rubber coverage.


Nathan: The Invincible Run 3, a neutral shoe, is unique regarding its stability elements. ZoomX typically is very soft, but this version feels more controlled and firm (relatively), particularly in the forefoot. Additionally, the ground contact in the heel and forefoot is very wide, with a typical width midfoot (with how wide the heel and forefoot are, the midfoot looks more narrow than it is). What I appreciate is that there is subtle rounding (beveling) on each edge of the midsole in the wider areas. This helps create a smoother landing regardless of where you land. Sometimes with significant flaring of the sole, it can lead to higher torque potential around the ankle at initial contact. The subtle beveling here seems to mitigate that as landing at any portion felt comfortable. The sole flare goes in both directions, helping people who want some structure on the outside or inside of the heel and forefoot, which may particularly suit someone who tends to move outward during their stride. There is also a firm rim that surrounds the heel counter between the upper, which seems to help the heel foam compress as a unit, making it less unstable. 

Andrea: The Nike ZoomX Invincible Run Flyknit 3 has a number of elements that could provide stability, depending on a person's biomechanics. Despite having a high stack height of ZoomX foam, this shoe is notably less bouncy and potentially unstable feeling as compared to Version 2. It has an extremely wide base that does not narrow significantly in the midfoot. It has extensive sole flare in both the rearfoot and forefoot, including a posteriomedial flare in the rearfoot. The extensive medial and lateral sole flare in the rearfoot and forefoot appear to be wider on the lateral aspect, which is a feature that I appreciate as someone who tends to land too far laterally. The heel bevel and forefoot rocker encourage forward motion from initial contact to push off. Personally, I found the shoe to progress smoothly from initial contact at the lateral midfoot to pushoff, but I found landing at the lateral midfoot to be firmer than I would like. 

Invincible 2 (teal) vs. 3 (pink)

Thoughts as a DPT: Invincible 2 vs 3
By Andrea Myers

The Nike ZoomX Invincible Run line has received mixed reviews from the DOR team over its three iterations. Matt returned version 1 because it gave him Achilles pain, while I loved version 2 for its bouncy ride and midfoot strike-friendly geometry. Invincible 3 feels very different to me then v2, and I definitely prefer the fit and ride of v2. For those who either loved or hated previous versions of the Invincible Run, I would like to discuss the differences that I experienced between v2 and v3.

I found that v2 fits a little longer than its stated size, while v3 seems to be fairly true to size in length. There is ample width in the toe box in both versions, although v3 feels like it has a little less volume. The most pronounced difference between the two is the fit in the rearfoot. As I mentioned above, v3 has less padding on the heel collar, a wider opening in the rearfoot, and the laces tie a little further down on the foot as compared to v2. While I had no issues with heel security in v2, I was unable to achieve sufficient lockdown in v3 despite multiple lacing strategies.

For me, I could summarize the performance differences between the two in one sentence: Invincible 2 feels more suited for midfoot or forefoot strikers, while Invincible 3 feels more suited for rearfoot strikers. Invincible 2 has a larger heel bevel, which tend to make midfoot landings feel more natural, as well as more a more responsive and bouncy midfoot landing. Invincible 3 feels bouncy and responsive in the rearfoot, which I notice when walking in the shoe, but midfoot landings feel firm and clunky for me. The smaller heel bevel of v3 also makes midfoot landings feel less natural because it feels like the rearfoot of the shoe gets in the way at initial contact for me. The vast majority of runners are rearfoot strikers, so I think these geometry changes will actually make Invincible 3 work better for more runners. The issue that remains is the lack of heel security, which I hope Nike will address in version 4.

Both shoes are neutral shoes, but they have elements that may provide mild guidance to forward motion, depending where an individual lands. Both shoes have a high stack height of ZoomX, which is a highly responsive foam that relies on the geometry of a shoe to provide some stability. Invincible 2 has a stack of 36.6mm/27.6mm in the men's version and 34.2mm/25.8mm in the women's version, whereas v3 is 40mm/31mm in both the men's and women's. Despite the higher stack in v3, it actually felt firmer and less bouncy at initial contact to me as compared to v2. This may be due to the extensive rubber coverage of the outsole in the v3 provides additional stiffness to the sole or the wider midfoot platform of v3. They also both have extensive sole flare in the rearfoot and forefoot, with the forefoot sole flare wider laterally than medially. This feature may work well for those who tend to land too far laterally at the midfoot. The rearfoot of v2 has a large heel bevel and posterior flare, which may make rearfoot landings feel less stable. Invincible 3 has a smaller heel bevel and a posteriomedial flare, which could make rearfoot landings more comfortable and stable. Lastly, v3 has a wider midfoot, which could contribute to a smoother transition from a rearfoot strike. Runners with significant stability needs will likely find both shoes too neutral for their needs, but runners who do well with neutral shoes will find v3 a little more stable than v2.


This one is obvious. Fix the upper lock-down issue. I think this could be done by modifying the lacing so it goes a bit proximally on the foot or through some additional cushioning in the heel counter. I'd love to experience this shoe with a better lockdown.

Andrea: The most important fix for this shoe is to fix the lockdown. I agree with Nathan that the best way to achieve this is to make the lacing come up further towards the ankle and to increase the amount of heel collar padding. I think the changes Nike made to the geometry of the shoe as well as the improved outsole have made this shoe more accessible for a greater number of runners, but if the shoe doesn't lockdown, nothing else matters. 


Nathan: The Invincible 3 is a workhorse trainer for those who like the feel of ZoomX and want a muted version for daily training. It is durable and breaks in well, but isn't quite versatile enough to be a stand-alone shoe for a training cycle that includes higher efforts. In comparison to the most similar option out there - the ASICS Nimbus 25 - the Invincible feels bouncier, firmer, and a bit more responsive. For someone wanting high comfort and cushioning, the Nimbus 25 is your option. The Invincible 3 is for those wanting a slightly firmer but bouncier feel, the Invincible is the direction to go. Either option gives you a protective feel and little ground contact.

Andrea: The Invincible 3 is a max cushion daily trainer that will work best for heel strikers without significant stability needs. Runners who land further forward who liked Invincible 2 may not like the changes to v3, which include a much firmer landing and a rearfoot that feels like it gets in the way. Any runner interested in the Invincible 3 should test it before buying to ensure that you can achieve sufficient lockdown. 



Fit: B- (Heel slippage an issue, a bit lower volume in the toe box than needed)
A- (Protective and durable for high mileage)
Stability: B (Neutral shoe that does offer some options for those needed lateral stability in heel and forefoot)
DPT/Footwear Science: A- (Always nice to see a top-notch foam made runnable)
Personal: A- (Really liking for daily runs and long runs despite the heel fit)
Overall: B+/A- 
Fit: B- (lack of heel security is a dealbreaker for this shoe, runs shorter than Invincible 2)
Performance: B 
(Ride quality greatly reduced by firm midfoot landing, heel getting in the way at initial contact, and heel slippage)
Stability: B (balanced sole flare, wide base, and reduced heel bevel and forefoot rocker give the shoe a centered ride)
DPT/Footwear Science: B (Compared to Invincible 2, v3 has a completely different ride and may be less appropriate for non-rearfoot strikers)
Personal: B (prefer the fit and ride of v2, although v3 may be a great walking/standing shoe)


Nike Invincible 3
Price: $179.95 at Running Warehouse

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Editor's Note: As always, the views presented on this website belong to myself or the selected few who contribute to these posts. This website should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your local running physical therapist. If you are in the Los Angeles area, I am currently taking clients for running evaluations.

***Disclaimer: These shoes were provided free of charge in exchange for a review.  We thank the people at *** for sending us a pair.  This in no way affected the honesty of this review. We systematically put each type of shoe through certain runs prior to review. For trainers and performance trainers, we take them on daily runs, workouts, recovery runs and a long run prior to review (often accumulating anywhere from 20-50 miles in the process). For racing flats we ensure that we have completed intervals, a tempo or steady state run as well as a warm-up and cool down in each pair prior to review. This systematic process is to ensure that we have experience with each shoe in a large variety of conditions to provide expansive and thorough reviews for the public and for companies. Our views are based on our extensive history in the footwear industry and years testing and developing footwear. If you are a footwear rep looking for footwear reviews or consultations on development, we are currently looking to partner with companies to assist, discuss and promote footwear models. Partnership will not affect the honesty of our reviews.

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