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Topo Athletic Ultrafly 3 Review
By Chief Editor/Founder Matthew Klein

People looking for shoes with wide, anatomic toe boxes are often limited to a few options. Most out there are zero drop, given that anatomic shoe design is often associated with more minimal or natural minded footwear companies. While that may work well for some people, others may need something a bit more traditional for a variety of reasons. Add looking for more traditional stability methods like posting and things get tougher. Enter the Top Athletic Ultrafly 3, a meeting point between natural and more traditional shoe design. A mild stability shoe with an anatomic toe box with a 5mm drop is a uniquely balanced shoe, particularly among today's extremes in footwear. 

Topo Ultrafly 3
$130 at Running Warehouse

Weight: 9.5 oz, 269 g (men's size 9), 8.4 oz, 235 g (women's size 8)
Stack Height: 25 mm / 20 mm
Drop: 5 mm drop
Classification: Mild Stability Daily Trainer


The Topo Athletic Ultrafly 3 is a mild stability daily trainer with a large anatomic toe box for those looking for some extra room without being zero drop. The stability comes from more traditional methods, specifically a heel counter and a mild medial post, while the addition of a filled-in midfoot and strategic flex grooves provide more new age methods. The Zipfoam provides solid and consistent cushioning, creating a stable ride for daily and long miles. A solid and secure upper sits up top, providing enough room for those who need a large toebox. The 5 mm drop provides some offloading of the Achilles, but isn't so high that it deviates from Topo's natural origins. The Topo Athletic Ultrafly 3 is a unique daily trainer for those wanting mild stability, an anatomic fit, a more traditional stack height and a moderate heel drop, meshing a variety of footwear design views together.


The Topo Athletic Ultrafly 3 fits me slightly short in my normal men's US size 10/UK size 9.5. The heel fits normally and it is easy to down with the laces. I had no security issues and did not have to lace lock the shoe. The heel is secure thanks to both an internal and external heel counter. I did not notice the heel counter on my heel bones as there is some cushioning in the heel collar that offsets the stiffness. The external heel counter is not intrusive at all and locks the heel in nicely. The midfoot is on the wider side and transitions into a wide and anatomic toe box. As someone with a more normal width foot, I did have to lock down the laces a little tighter on turns, but the midfoot responds well to the laces and was fairly secure. The tongue is moderately thick and is not gusseted. It is secured at the top of the foot by the laces, which actually does a great job of keeping in place. The sockliner and inner liner of the shoe is comfortable enough to be used sockless. Half my miles have been sockless in this shoe and I had no issues with chaffing. Those interested in a comfortable upper for sockless wear should look here!

Overall the fit is on the wider side, especially in the midfoot and forefoot, although it does run slightly short. Those wanting a wide anatomic toe box will enjoy the Ultrafly 3, while others will need to make sure they lock down the midfoot with the laces.  


The Topo Ultrafly 3 is a daily trainer with a cushioned but firmer foam underfoot. There is a mild rocker shape to the sole, with more toe spring and a smaller heel bevel. The ZipFoam is protective, but is on the firmer side. This feel is consistent throughout the sole and makes this shoe best for daily training miles but not uptempo/speed work. The heel bevel is more lateral, providing a quick transition forward that feels a little slappy until the shoe breaks in. The midfoot transition is fairly smooth thanks to the wider base. The forefoot is also fairly smooth thanks to the toe spring and mild flexibility creating a smooth transition during toe off. The forefoot is not the most flexible thanks to the stiffer sole, but a few flex grooves do add some amount.

There is a 5 mm heel drop that feels closer to 6-7 mm. It isn't super high, but does not feel low enough that it bothers my Achilles or works my calves extra. The drop feels right in the middle between high and low. The toe spring helped the transition, so those looking for a wide toebox shoe with a little more drop may find some success here. The mild rocker and firmer ride more inherent stability, but the ride is best for easy miles, recovery runs and long runs for those used to more traditional stack heights. The ZipFoam as mentioned is protective, but is not the most responsive. The heel transition improves slightly with more uptempo paces, but the Ultrafly 3 is meant more for mileage than workouts. The durability is fantastic. I have 35 miles on my pair without any major wear (except some mild dirt).

These shoes are best on road or light well maintained trail. The outsole does not have the most traction, so different options would be preferred in the Topo Athletic line for more aggressive trails. Overall the Topo Ultrafly has a mild rocker and a firmer sole that works best as a daily mileage shoe.


The Topo Athletic Ultrafly 3 is a mild stability training shoe. There is an external TPU heel counter that wraps around both sides of the heel, providing guidance forward for those that heel strike. There is a traditional medial post that runs from the heel to the midfoot. This post also fills in the midfoot, which stays wide and further contributes to stability. The wider forefoot creates a stable place to transition from and the toe spring rolls you forward. The heel counter was not noticeable, but the mild post is. There was a solid amount of pressure into my medial heel that I got used to as the shoe broke in. Those who are sensitive to posting may need to approach this shoe cautiously, but those who are searching for it will love this shoe. The midfoot is particularly stable given both post and the post filling in the medial aspect of the it. The post is not intrusive here, but contributes to the great midfoot transition into the forefoot. Overall the stability is mild to almost moderate in this shoe. Those sensitive stability will definitely notice it, while those looking for a stability shoe with a post will be happy to know it is noticeable in the heel but integrates well into the midfoot.


The Topo Athletic Ultrafly 3 offers a unique design in that it brings together many elements that are often exclusive. To have a more "minimal" or natural shoe with a traditional post and some heel drop is rare. It has become a go to recommendation for me for certain people, usually non-runners, looking for something that has enough room in the midfoot/forefoot to offload things like Morton's Neuromas (which sometimes occur due to compression of the distal nerves of the feet between the metatarsals/phalanges) without being an extreme barefoot inspired shoe with no cushioning or heel drop. Not everyone does well with zero drop shoes as they often require adequate calf range of motion and strength that many people are lacking. While everyone should work on those, finding something that provides some quick relief without creating another problem is difficult when it comes to shoes.

Many shoes on the market today come in wide, but rarely are they anatomic. Frequently, these shoes tend to have more volume than width, which can make for a sloppy fit. Additionally, the widths often create volume in areas that only work for certain people. It has been my experience that wide shoes in the US tend to increase volume in the heel and midfoot, while wide shoes over in Japan tend to increase it in the forefoot. This is why I previously ordered wides from Japan (prior to the current issues with international shipping) as I got to experience shoes like the Adidas Adios or Tempo with more volume in the forefoot, where I needed it at that time. Frequently, the only option when it comes to finding shoes that are anatomically shaped are minimal shoes or Altra shoes. While Altra does a great job with a variety of cushioning levels, the zero heel drop can be limiting for some people who may have Achilles tendon or calf problems. For those who want an anatomic toe box in a shoe that is not zero drop, the Ultrafly 3 may be a good option. Although 5mm is still on the lower side of a moderate heel drop, it is still enough that many people can transition into it from more traditional levels without too much risk.

The final interesting part about this shoe is that it has an anatomic fit but still has a traditional stability method like medial posting. It may seem that we criticize this method, but it is effective for certain people. What we criticize more is not using a variety of stability methods as most people respond better to certain things compared to others when looking for it. An example being that some people may find geometric stability or other types of new age stability methods not enough for them to feel supported, whereas a shoe like the Ultrafly 3 has a post that is noticeable. That feeling of pressure into your foot is a big positive for many people, especially those who may be using these shoes for other things besides running. The Ultrafly 3 does use a post, but also uses an external heel counter that wraps both sides of the foot and a wider midfoot. Both of these are less traditional and add elements of what we call "stable neutral shoes." One method is not globally better than the others. People respond differently to different methods, thus having at least a small variety is important to meet the needs of different individuals.


The stability elements are integrated well into the Ultrafly 3 and provide a unique offering of a shoe with a wide anatomic toe box and mild stability, particularly through a medial post. The biggest suggestion I have is to soften the sole. The ZipFoam is fairly firm, which would be great in a lighter, more workout oriented shoe. However, as a daily trainer, it may be beneficial to have a slightly more forgiving sole. This would also help with the heel transition, making it less snappy and reducing the need for a larger heel bevel. If it is to be kept the same, which may be understandable for stability purposes, then I would increase the lateral heel bevel depth. This is known to reduce the rate of pronation and will improve the transition, so will make the rearfoot ride smoother and add additional stability for those who need it medially. Outside of that I think this is a great unique shoe that has been a go to recommendation for those who need mild stability, a wider anatomic toe box but need some heel drop. 


The Topo Athletic Ultrafly 3 is a anatomically shaped, mild to moderate stability daily training shoe with some heel drop. The upper fits securely in the heel while opening up in the midfoot and forefoot. Those who want more width and an anatomic shape up front will do well here. The stability comes from a medial post in the heel and midfoot, but also from an external heel counter, a mild rocker and a wider midfoot. Posting in a more natural and anatomic shoe is rare, so this is an interesting combination. The ZipFoam midsole is firmer and lends itself to daily training miles and long runs on road. While not the fastest foam, it is protective, durable and consistent over long miles. The Ultrafly 3 also is an optimal walking/work shoe for those who need more room with a little heel drop and some stability. It is one I have frequently recommended clinically for those who need an anatomic forefoot and some support while still needing some heel drop. So those wanting a unique and consistent mild to moderate stability shoe for daily training miles may want to take a look at this shoe. 


Fit: (Wide toe box but fits slightly short. Good heel security but requires extra lock down at midfoot/forefoot. Comfortable inner liner for sockless running.)
B-/B (Solid shoe for mileage. Smooth forefoot but clunky at the heel. Firmer ZipFoam protective but not responsive)
Stability: A- (Excellent mild stability with noticeable medial post. Bonus points for using post to fill in midfoot)
DPT/Footwear Science: B+ (Solid use of multiple stability methods, but would benefit from additional heel bevel to smooth out heel transition)
Personal: B (Comfortable for walking/clinic use. Slightly clunky heel less fun for mileage for me. Getting more forward on the shoe is comfortable, but also fits slightly short for me)
Overall: B/B+ (Solid and unique shoe. Wide toe box with mild stability and some heel drop will be an excellent balance for those looking for all three.)

Find the Topo Ultrafly 3 at Running Warehouse here.
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Doctor of Physical Therapy
Board Certified Orthopedic Clinical Specialist
Fellow of the American Academy of Orthopedic Manual Physical Therapists

Dr. Matthew Klein is a 150 lb male with notable PRs of 14:45 for 5k and 2:32:44 for the full marathon.  He typically runs 70-100 miles per week and trains at a variety of paces from 8min per mile recovery runs to 4:40 per mile 1k repeats.  He prefers firmer and responsive shoes with snug heels and medium to wide toe boxes.  The stability guy of the group, he also prefers a little stability in his footwear. However, as a researcher, clinician and running shoe aficionado, he will run in anything. 

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 Topo Athletic 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 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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