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 PUMA Liberate Nitro Review
By Nathan Brown

The PUMA Liberate Nitro is the lightweight performance trainer in PUMA's resurgence in the run specialty scene. The market for lighter weight shoes with supercritical foams is booming due to runner preference in this direction, and many people are leaning towards using these types of shoes not only for speed work, but for all training due to the fun yet protective feeling that some of these "new-age" foams that are hitting the market. The Liberate is the stripped down, lighter performance trainer sibling of the Velocity Nitro from PUMA, the brand's versatile daily trainer.

Specifications (per PUMA)
Weight: 6.3oz/179g (men's size 9);  5.2oz/148g (women's size 7.5)
Stack Height: 28mm (heel), 18mm (forefoot)
Drop: 10mm
Classification: Lightweight trainer


The PUMA Liberate is a lightweight trainer that features the supercritical NITRO foam, giving it nice cushion and protection in the heel and transitioning to a firmer toe off. The Liberate is flexible throughout and a very natural feeling shoe that gives ground feel and comes in light enough to really push the pace. In a way, this shoe is a lot of what I hoped the Reebok Run Fast 3 [REVIEW] would be.


The Liberate has a true performance fit, where it is narrow through the midfoot and toe box to hold the foot nice and snug. Length-wise, I actually found the shoe to fit slightly long (1.5-2 thumb widths) compared to the other shoes in the line-up that I've tried (Velocity and Deviate Nitro Elite). There were times when pushing the pace that I would feel the extra length during toe off and did affect how smooth propulsion was (more on that below in the next section). Overall, the upper lives up to the "Liberate" name, with minimal reinforcements and flexible materials.

The upper really consists of two layers. The first and most visible is the very thin mono mesh upper that is akin to the one seen in the Deviate Nitro Elite, which in my opinions is the most comfortable mono mesh upper out there and laces down extremely well. My version, the wicked snazzy COOLadapt green colorway, is also said to have COOLadapt tech within the upper to keep the foot cool (not sure how it's supposed to work, but as you'll read didn't really for me). The second layer is what the midfoot and forefoot come in contact with, which is the gusseted tongue that spans the entire toe box. This is a very soft material that is comfortable on the foot. However, with the more narrow fit to begin with, this inner portion of the upper, in combination with the midfoot "straps", can feel quite snug and gave unwanted pressure across the sides of my feet. After the first 2-3 miles in a run, this would decrease and I could finish a 10 mile run without an issue, but I would experience the early tightness/discomfort each run. Despite the thin mono mesh upper and COOLadapt technology, I actually found the shoe to run a bit warm and had some issues with more sweating than normal. To be fair, we are transitioning to spring here in Wisconsin, so part of this could be my body adapting to the heat as well.

The heel is minimally reinforced, with no formal heel counter but there is a more rigid "bar" that sits vertically at the back of the heel to provide some structure. I had no irritability from the heel bar at all. The rest of the heel cup is a thin material with some padding on the inside and outside of the heel to protect the achilles and provide some security. I did not have slippage at any point, but the upper rim of the opening of the shoe did become a bit "sloppy" even after 10 miles, which made it fit a little looser. 

Project Fit
Check out how the Liberate and Velocity Nitro has fit other runners in the IG post below!


The Liberate lives up to its namesake. This is a very free riding shoe without much structure. I think of it as a Kinvara with a supercritical foam, a lighter/quicker Run Fast 3, or a Razor 3 without as much of a rocker. Heel strike is quite cushioned and smooth, and then you quickly transition to a much firmer forefoot for toe off. This firmer toe off and flexible midfoot (due to the lack of outsole coverage) give a good amount of ground feel despite the supercritical foam, giving it a crossover between what feels like "natural" running tempo days and new age foam. Another factor that gives it a natural feel is that the rocker in very minimal. The shoe transitions over a flat but flexible platform instead of a rolling rocker sole.

I took the liberate both on hard tempo runs (8+ miles) and on recovery runs. Given the protection in the heel, it actually performed well for recovery days for me and worked well for recovery days where I still wanted to feel more connected to the ground. But the shoe really comes alive for tempo work. A really light 6.3oz, a somewhat bouncy heel for quick transitions, and a firmer toe off allow the shoe to come with you for longer tempos, fartleks, and track work (feel good on track with the PUMA grip and lower profile). 

I wanted to return to the length comment from above. For me, this shoe fits about 1/5-2 thumbs width from the end of my longest toe. When really starting to turn over I found that this extra length would "fold under" a bit and disrupt the smooth toe off. However, I wouldn't want to size down given the more narrow fit. The length isn't a deal breaker by any means, but toe off at faster paces could be improved upon with a better fit or some geometry changes (for me). 


This is a very flexible (can fold it in half at the midfoot) shoe, making it a truly neutral shoe. Yes, the slightly lower profile, typical shaping/lack of extreme rocker, and full ground contact help with some stability, but people who will do best in this shoe will have good strength in their legs and feet to transition well over a flexible platform. That said, PUMA does add a TPU plate in the heel (doesn't extend too far in), which gives some stability for landing as a heel striker as it decreases the side to side flexibility. Anything forward from the most posterior part of the heel is very flexible. The other aspect that I appreciate from a stability standpoint is how secure the upper is. There was no feelings of slipping of my foot on the platform, which made this a great option for track workouts and running in areas with more turning.


The Liberate, again, lives up to its name and provides a flexible and natural design that may demand some stability due to its delightfully free and flexible design. Therefore I wanted to touch on a few of the muscle groups to consider that help provide stability in the foot while transitioning through the gait cycle. This isn't an exhaustive list nor does it give a list of all of the muscles' roles the ways to train them, but serves as an intro. Also, working on these muscles is a good idea for pretty much anyone regardless of the shoe you're running in. Let's start from the bottom up.

  • Foot Intrinsics: Our foot actually has 4 layers of muscles that run through the foot, and (depending on how you count them) 11 muscles that start and finish within the foot itself. These 11 muscles help give stability to the medial and lateral arches of the foot and support the passive structures (spring ligament, plantar fascia, etc) as well as the tarsal bones. To work on these muscles, check out our Run Performance article on Foot Intrinsic Muscle Training.

  • Tibialis Posterior and Peroneus Longus/Brevis: These two muscles (along with a few others) act as "stirrups" around the ankle joint and also provide dynamic control of the arches of the foot. One way to train these is to practice single leg balance, particularly on uneven surfaces like the dome side of a BOSU ball. Doing balance training like this 2x/week can be helpful in developing ankle stability. Also check out our Injury Prevention article on Ankle Stabilizers for some more ideas.

  • Gluteus Medius/Maximus: Believe it or not, the stability of the foot, our arches, and our ankle also depends on the strength and stability of our hip. In short, external rotation of the hip is coupled with supination of the foot and internal rotation of the hip is coupled with pronation of the foot (a bit more complex than this...but that's for another time). Therefore if you have weakness is muscles that control external rotation (or abduction...which can lead to increase internal rotation of the hip indirectly) you can have less stability through the foot when absorbing shock. Check out our Injury Prevention articles on the Hip Stabilizers for ideas on how to work on them (Hip Abductors | Hip External Rotators | Hip Extensors)


There is a lot that works well with this shoe, and the ride is a great combination of natural and fun/bouncy. My biggest recommendations come down to fit -- which I admit are very individualized -- so these should be taken with a grain of salt. The first would be to hone in on the heel/ankle collar. It simply got sloppy early on and it would be nice to have something a bit more structured. Second is the length/width ratios. I think the extra length interfered with a smooth toe off, and the narrowness gave some discomfort to the foot. The width adjustment may be as simple as changing the thickness (or removing) the medial and lateral "straps" that wrap the midfoot. That is where the discomfort was and there are 3 layers of upper in that region. Another possibility for helping with toe of is giving a little bit more toe spring to the shoe to help roll off a little easier. However, the shoe is so flexible that I'm not sure how much this would adjust the actual ride. 


The Liberate is a flexible and "natural" feeling shoe with some ground feel that still gives you some protection in the heel with the bouncy supercritical NITRO foam. For those wanting a lightweight trainer that can handle both moderate distances and workouts on the regular, this could be a nice option that comes in at $110. As noted above, the flexibility will put more demand for stability on the runner, so this will work best for efficient and stronger runners. 


Fit: (tight in the early toe box and fit long, but really great lockdown and very comfortable/light upper)                     
Performance:  (Fun and rather versatile ride, really light on the foot, functional for lots of different workouts and even daily miles) 
Stability: B- (Lower profile helps as well as full contact and the TPU heel piece, but the flexibility puts much foot stabilization demands on the runner) 
Personal: B+ (If the fit was there for me, it would be an A because it's a really enjoyable ride and versatility is there)     
Overall:  B+ (Solid lightweight trainer option for those who want flexibility with some fun NITRO foam)     


Compare Trainers
Puma Velocity Nitro -
Liberate's older sibling. The full on daily trainer from Velocity is a team favorite
Hoka Mach 4 - Hoka's big redesign has been a fan favorite. Light, fast, and fun.
Saucony Kinvara 12 - Saucony's modern classic lightweight trainer goes back to its roots for the 12th edition
On Cloudflow 2.0 -
On Running's lightweight trainer for those who like a firm ground contact shoe that rolls with ease
Saucony Freedom 4 - Injected with PWRRUN PB, the Freedom 4 is a versatile, uptempo shoe that can potentially be a racer for those looking for an exciting none-plated offering
Reebok Floatride Energy 3.0 - Smooth, soft miles at a fantastic price point

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Thanks for reading!


You can find the Puma Liberate Nitro here at

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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. IG handle @kleinrunsdpt

Dr. David Salas is a 135 lb male with notable PRs ranging from 3:54 in the 1500m to 1:08:36 for half marathon. He typically runs 60 to 70 miles per week and trains from about 7:30 recovery runs to fast shorter efforts at 4:30 pace. He normally prefers neutral shoes with a firmer ride, but is completely open to other types of shoes.  He is a footwear enthusiast at heart and will always appreciate a high quality shoe when it comes around. For updates on training or testing, IG handle: @docsofrundavid

Dr. Brown is a 155 lb male with notable PRs of 18:18 5K, 39:25 10K, 1:29:01 half marathon, and 3:54 marathon. He typically runs between 20-40 miles per week at a variety of paces from 7:30-8:30 min/mile for recovery runs to 6-6:45 min/mile for tempo runs. He typically prefers shoes that provide some cushioning underfoot but still maintain a more firm and responsive feel. Current goals for 2020 are to break the 1.5 hour half marathon and 3:30 marathon. IG handle: @nate.docsofrunning

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.

Doctor of Physical Therapy
Board Certified Orthopedic Clinical Specialist
Fellow of the American Academy of Orthopedic Manual Physical Therapists

Nathan Brown PT DPT MS
Doctor of Physical Therapy 
Masters in Anatomy and Clinical Health Science
Movement Performance Institute Certified in Advanced Functional Biomechanics 

David Salas PT DPT CSCS
Doctor of Physical Therapy
Certified Strength and Conditioning Specialist

Bach Pham MS
Marketing and Social Media Manager
Master of Arts in Cultural Anthropology

***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 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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