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Zen Running Club ZR-01: The Future is Sweet
By Content Manager Bach Pham

In our recent launch of our sustainability series, we started exploring what the running industry is doing to move towards a sustainable future. Zen Running is one of many new brands that have hit fast forward in order to solve the running shoe industry problem not down the line, but now. In their first major release, the ZR-01, they've launched a brand new product featuring a shoe that runs on a sugarcane-based midsole.

Price: $139 at Zen Running
Weight: 10.06 oz, 286 g (men's size 9), oz, g  (women's size 8)
Stack Height: 33mm heel, 24 mm forefoot
Drop: 9 mm drop
Classification: Daily Trainer


The Zen Running Club ZR-01 is a higher stacked, rockered daily trainer that is composed of sustainable materials throughout the shoe. The ZR-01 features a lightweight knit upper made from eucalyptus fibers, a castor bean foam insole, sugarcane based midsole, and natural rubber outsole. Sustainable components aside, the shoe features many modern design touches with a rockered ride, a generous 33 mm heel, 24 mm stack height, and a generous amount of sole flaring in the heel to create a decently stable ride. Zen Running's ZR-01 is one of the few truly sustainable shoes to match eco-friendly materials with contemporary design to create a solid daily trainer built with the future in mind.


Zen Running recommends runners to go half size up from their traditional sizing for a regular fit and a full size up for wider feet. I found the shoe to fit very well with a half size up and agree with their assessment. The eucalyptus fiber knit upper is one of the most comfortable versions of knit I have had on foot. It's soft, fairly breathable for a knit upper and over time has only gotten more comfortable as the material has adapted to my foot. The double pull tabs work extremely well in help you slide your foot in comfortably. I loved the pink accent this particularly pair provided with the pull tabs.

There is no heel counter or structure of any kind; the upper is so minimal that you can press the whole upper down into the shoe. It being unstructured, there's a touch of volume in the forefoot to let the toes breath which is a plus. The shoe laces up well enough, but could use another eyelet for lace-locking to improve the heel fit. It is a very relaxed fit as is, which makes the shoe feel best for daily training paces. The insole is also removable for folks who want to use their own.


So what does sugarcane feel like? There's no doubt that EVA is the closest comparison. The ride leans firm, but having such a high stack of it does mean you aren't feeling road either. The rocker does a nice job of keeping you rolling forward. The best comparison for the midsole is something akin to Saucony's PWRRUN as far as underfoot feel. This is certainly not a superfoam, but that's not the goal here either.

The ZR-01 is best at easy to recovery paces, providing plenty of protection for long mileage. When picking up the pace, the combination of the rocker and moderately high stack feels average at best. The relaxed knit upper doesn't quite provide enough security to really dial in faster running in this model, especially with the midsole being a bit heftier than the upper. It takes a bit more work to turn over quickly if you do want to do extended workouts in this. For the majority of your running though, the ZR-01 feels plenty protective and does an excellent job at its primary function of eating miles. I took the shoe out for many easy runs and a long two hour easy paced effort with no issues. The forefoot rocker is lightly flexible and feels good to load and push through. There is a posterior heel flare that extends a decent amount back. There is just enough bevel that I never felt it to be an issue on my run, but it is something to note if you know it is typically something that is a problem.

The outsole has very good grip and has more than enough protection for light trails at easy paces. It also has been plenty durable so far. I expect a solid lifespan out of the ZR-01.

Lastly, the shoe is quite comfortable for everyday walking. It is a little too unstructured for lateral movement activities like basketball and volleyball though due to the upper and design focused on forward movement.


The ZR-01is a neutral, high stacked shoe that has a decently stable design thanks to tremendous sole flaring in the forefoot and heel acting as the primary force in stabilizing the model. A full ground contact outsole and crash pad in the heel in tandem with the rocker design does a good job of working together to guide you forward.

There are still three areas that keep this relatively neutral though: the taller stack height, relaxed fitting upper, and tapering midfoot on the medial side. The combination of the looser upper and narrowing medial midfoot makes the shoe not necessarily unstable per se with the elements in place, but possibly uncomfortable for anyone who has severe medial needs - especially those who typically rely on shoes with posting as there is just a lack of midfoot present when landing. The stack height is also tall enough that if you lose control the upper and shoe does not have much in terms of "saving" you, which is why I strongly feet that the shoe shines as an easy day trainer.

On the run as a flat foot runner, while it was not an issue stability-wise, I could feel the shaping of the midfoot and how it was curving in under my arch. It's an unusual sensation that wasn't a discomfort per se, but a notable feeling - similar to how Hoka sidewalls sometimes are present for individuals.

Credit to Zen Running for implementing the sole flaring though, which does make a significant difference in helping the shoe be relatively stable.


Softness vs. Comfort, Design Over Desire
By Content Manager Bach Pham

Recently I slipped on a pair of Vaporflys for the first time and just did a quick jog out the door. The ZoomX midsole was undoubtedly totally different from many of the recent shoes I've tried: a bouncy, yet soft and marshmellowy texture. Coming from everything including the lower stacked New Balance Tempo v2, firmer stability shoe the Wave Horizon 6, retesting of the Hoka Kawana, and others, the Vaporfly felt like a shoe from outer space.

We get asked a lot at Doctors of Running about how soft or firm a new shoe is. Recently in our Pegasus 39 Sub 2, Nathan talked about how we can perceive shoes differently due to recency bias. Maybe you've been running in a lot of firmer or softer shoes, so when you try an opposite the feeling feels particularly exaggerated. We're in a unique place at Doctors of Running where we are testing so many shoes, our range of feeling can be wildly different throughout the year. Other elements like weather could also be impacting how we perceive soft vs. firmness based on the shoe. A firmer shoe, for instance, may feel pretty darn firm in the winter on cold roads while the same shoe may be perceived as moderately firm to even slightly soft on warm roads. This is just something we have to dial in and keep in mind while testing.

While we talk about softness vs. firmness often, we often miss that comfort can mean something totally different to others. How soft a shoe feels underfoot doesn't necessarily mean how comfortable a shoe is depending on the runner. For me, an ultrasoft shoe can feel far too unstable for my needs, which makes it far less comfortable than a slightly firmer shoe like the Pegasus or the ZR-01 which many would label each as leaning firm. That slight firmness, however, provides me a comfort of feeling stable when landing on the ground and taking off which makes the shoe ultimately much more comfortable and suitable for my needs. Though the ZR-01 is likely going to be perceived as firm, that didn't mean I did not feel that the shoe was poorly cushioned. The shoe has a healthy stack of midsole that undoubtedly felt protective and capable of taking care of me for miles on end.

We have an obsession with asking for shoes to get softer and softer, but we have to keep in mind that it's not just about how soft a shoe can get, but how all the elements work together to create the intended performance goal. The Endorphin Speed, for instance, is a great example of a shoe that only moderately leans soft, but is very well tuned with some minor rigidity from the plate, a well-fitting upper, and excellent speedroll design to help create a very enjoyable performance shoe that is well-loved.


The primary recommendation I have for the ZR-01 is regarding the upper. A few things like extra eyelets to help lace lock the shoe and a slightly more secure heel would help add a lot of performance to the shoe for Version 2 and add just a touch of versatility. It would help to make the weight feel balanced as well. If there was ability to tune the sugarcane midsole to be lighter as well, that would impactful. I would also like to see the midfoot filled in to help smoothen and fully stabilize the ride - but only if they can also dial the weight of the midsole down. A very similar shoe to the ZR-01 is Craft's Ultra 2 which does widen the midfoot and help make the entire heel-to-toe transition feel clean.


The Zen Running ZR-01 is an ideal daily trainer for anyone looking for a high stacked, slightly firm, rockered ride that is fully sustainable. At $139, the shoe comes in at an excellent price point compared to brands that only integrate mild sustainable components at a much higher cost. The shoe provides a very comfortable, relaxed upper that is well suited to log easy to recovery miles. Runners who are familiar with shoes like the Craft Ultra 2 or even Nike React Infinity Run will find a very comparable trainer in the ZR-01. As far as sustainable, quality footwear goes, Zen Running should be at the top of your list in terms of a shoe that delivers both modern performance with an eco-friendly design that's several years ahead of the game in that department.


Fit: B+ (A very comfortable fit for daily training with a highly breathable upper. Lockdown in midfoot through heel could be improved to add more performance though. Also be weary of sizing based on your needs (half size up regular, full size for wider feet)
B+ (Solid rocker ride with a firm, but protective midsole for easy to recovery paces. Lacks versatility, but will absolutely crank out your daily mileage)
Stability: B+ [Neutral] (Sole flaring on heel and forefoot helps manage the higher stack height. Slightly curved medial side along with relaxed upper will likely not suit severe pronation needs)
DPT/Footwear Science: A (Excellent use of sustainable materials implemented to create a modern running shoe)
Personal: A- (Considering that I was running on sugarcane, this was a very capable trainer that can compete against most high cushioned, rocker trainers in the market. The fact that it is sustainable is a big deal in terms of how well it also performs)
Overall: B+ (A reasonably solid daily trainer that will suit manner, and with more attention potentially push others to explore what Zen Running is doing in terms of sustainability.)


Price: $139 at Zen Running

*Using the link to purchase helps support Doctors of Running. Thanks so much!

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Find all Shoe Reviews at Doctors of Running here.

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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 Zen Running 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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