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Nike Air Zoom Alphafly Next%2 Review: Steady as She Goes
By Senior Contributor David Salas

The Nike Alphafly Next% 2 is a new generation racing shoe and a continuation of the somewhat polarizing first version. The Alphafly was a racing shoe that was loved by many, and also avoided by many. The shoe was a little bit on the heavier end, but provided good responsiveness with ZoomX, a carbon plate, and the Zoom Air pods in the forefoot. The shoe gets a tiny bit heavier, but integrates some improved sidewalls and wider, more continuous forefoot to create a more stable ride throughout. 

Price: $275 at Running Warehouse
Weight: 8.4 oz, 238 g (men's size 9.5)
Stack Height: not provided (others have noted 40mm/32mm)
Drop: 8mm
Classification: Road Racing Super Shoe


The Alphafly Next% 2 is a top shelf racing option that leans towards the longer distances. My pair, Men's 9.5, weighs 8.4 ounces, which is heavier from 8.1 ounces in my originals. The shoe still provides a sense of bounciness and responsiveness, though with a little more structure underfoot. The shoe is still a racing shoe, but feels a little less "fast" and more of a shoe that is rhythmic that you can have on your feet for a long time. The Alphafly Next% 2 is a racing shoe with some decent stability elements that can easily tackle a marathon and half marathon.


The Alphafly Next% 2 utilizes Atomknit 2 as the material for the upper. The mesh upper fits to the foot pretty well and has some decent resemblance of the first model. The upper feels like it has a little more natural reinforcement in the new model with the fibers being a little tighter woven and more resilient to stretch. The material also feels a little less synthetic and plastic like compared to Atomknit 1. The heel and midfoot are normal width with the forefoot being normal to slightly wide. The heel is curved backwards to allow some room for the Achilles and has some padding at the top to prevent irritation. The shoe did have some heel slippage initially, but when locked down the slippage minimizes quite a bit. Overall, the dimensions are done pretty well and the added sidewalls with midfoot widening on the platform makes for a more comfortable midfoot than the previous version too.  


The Alphafly 2 was an interesting experience. The shoe gained a little bit of weight, but maintained much of the same DNA. The biggest thing I noticed was that the shoe felt much better at rhythmic paces to me in Version 2. The forefoot widened slightly and the shoe has a little bit more ZoomX midsole at the air pod. The pods did not feel quite as abrupt and the midfoot transition felt smoother thanks to the sidewalls. The shoe feels a little more put together and less decoupled. This did come with a weight gain to an already heavy racing shoe. The Alphafly 2  feels like it lost some top speed for me, but the shoe is even better at rhythmic pacing.

This is easily a marathon option and potentially a good half marathon shoe as well. The pods are still noticeable and the forefoot bounce is still evident, though the rolling sensation is slightly more pronounced in this version. The ride ultimately feels more balanced throughout, though loses some top speed responsiveness.


I think the Alphafly Next% 2 made some good improvements in the stability category. The shoe utilizes geometry and sidewalls in a more efficient fashion than the previous version. The forefoot has also been widened and extended proximally to become more continuous with the midfoot. The shoe added a little bit more ZoomX foam above the air pod and streamlined the sidewalls through the midfoot. The results in a much more secure feeling when transitioning from the heel through the toe. The upper also seems to have some improvements with stability as well. The new Atomknit 2 seems to have slightly more continuous fibers that does not stretch quite as easily. The heel may have a little more room than I'd like, but locking the shoe down a little tighter seems to do the trick. For being a newer generation raising shoe, the stability of this model has actually done quite well. There is still some inherent instability with the soft and bouncy nature of the midsole, however the integration of sidewalls, sole flaring, and improved geometry seem to work well with the platform and my mechanics. 


Moriyasu, Nishiwaki, Yamaguchi, & Hokkirigawa (2012) looked at outsole pattern with different materials to compare the relationship of friction coefficient and ground reaction force. They found that there was a significant difference on friction coefficient between different surfaces and that the majority of differences were seen 80% into the stance phase of running and as slipping as early as 50% into the stance phase. The study compared relatively polar outsole designs, though it does show that friction coefficient can give us some insight into the shoes' relationship with the ground and ultimately stride. 

One of the changes that came to the Alphafly Next% 2 this year was the outsole design.
The forefoot itself appears to be extended proximally towards the heel a little bit more than the previous version with the hoof looking area a tad wider. They changed the traction pattern on the outsole with multidirectional rubber pieces with what they found in their independent labs to help with traction and performance. From experience the Alphafly Next% 2 does feel a little more stable and confident all-around with the ride and traction when transitioning through the midfoot and forefoot.


Moriyasu, K., Nishiwaki, T., Yamaguchi, T., & Hokkirigawa, K. (2012). Experimental Analysis of the Distribution of Traction Coefficient in the Shoe-Ground Contact Area during Running. Tribology Online (7) 4. 267-273


Though I really enjoyed my experience with the Alphafly Next% 2, I do have some recommendations. I do think the upper kind of still needs to be worked on to help with heel security. The midfoot and forefoot, however, do appear to integrate with a platform much better than at previous version. I think the shoe can also lose a little bit of weight as it is now close to 8.5 ounces in my current size and is starting to feel like a lot of shoe. It still works great for marathon and potentially half marathon though. 


The Alphafly Next% 2 is a premium racing shoe that provides a lot of modern innovations in a decently versatile package. The shoe certainly caters to the longer distances being marathon and half marathon. It runs much more stable than previous version with good sidewalls through the midfoot and features a more fluid forefoot by integrating the air pod, midsole, and plate better. The Alphafly Next% 2 doesn't feel as "fast" as its predecessor, but it is smoother and something you can certainly run a controlled, fast pace in for a long time. 


Fit: B+/A- (Instep really tight but helps hold foot, heel a little loose in the back and slips if you don't lock down well)
A- (Really good at longer distances and controlled efforts, though loses some top speed for 10k and down)
Stability: A- (Really good for a super shoe. The only thing here that could be worked on is the heel security in the Achiles area)
DPT/Footwear Science: A (I like that the changes to V2 are noticeable and appear thought out. The midfoot and forefoot integration much better and my midfoot doesn't hurt in this model after a few miles.)
Personal: A- (Definitely a shoe I will consider racing in going forward for marathon and half, though not the fastest feeling shoe)
Overall: A- (A solid long distance racing option for those that may need a little bit of stability or a wider platform)


Price: $275 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 purchased via discount in exchange for a review.  We thank the people at Running Warehouse 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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