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Saucony Endorphin Pro 3: Third Time's a charm
By Chief Editor Matthew Klein and Contributor Andrea Myers

The Endorphin Pro 3 has been updated with an additional 4mm of PWRRUN PB, bringing it just under World Athletics' limit of 40mm stack height for marathon racing shoes. Previous versions of the Endorphin Pro were known for their rolling sensation as opposed to a bounce. Does 4mm of foam really make a difference in the performance of a shoe? We were excited to find out.

Price: $225 at Running Warehouse
Weight: 7.2 oz, 204g (men's size 9), 6.2 oz, 176g (women's size 8)
Stack Height: 39.5 mm / 31.5 mm
Drop: 8mm
Distance Racing Shoe (Super Shoe)


Matt: The Saucony Endorphin Pro 3 is a fast, bouncy, max stack height, carbon fiber plated distance racing shoe that truly has achieved a "super shoe" status. A maxed-out midsole features 39.5mm/31.5mm of PWRRUN PB, providing a bouncy and fast ride. A snug but comfortable upper provides a highly secure and incredibly breathable fit. A new midsole geometry provides a guided and inherently stable ride. Combined with a new, lighter weight, all this together makes for an extremely fast, yet comfortable shoe that has the comfort for the marathon and the responsiveness/speed for some down to the 5k.

Andrea: The Saucony Endorphin Pro 3 is the best Pro yet. The additional 4mm of foam gives the shoe the bounce it had been lacking in versions 1 and 2 while maintaining the smooth ride from Speed Roll (rocker sole). The updated mesh upper is one of the most breathable on the market. While I found the previous versions too stiff for a marathon, I would seriously consider using the Pro 3 due to its updated geometry and ride.


Matt: The Saucony Endorphin Pro 3 fits me true to size in my normal men's US 10. The fit is snug throughout the length of the shoe, with a little extra room in the forefoot and a taper at the toes. The mesh is thin but mildly stretchy, so those with normal to narrow feet will do well here. The tongue is thin with holes throughout its length and is secured well by some gusseting around the arch. This midfoot wrap holds the foot down well to the platform and I did not have to lace lock the shoe. There is a small but moderately flexible heel counter in the rearfoot. There is some mild padding there and I had no trouble with it even over longer efforts. Those that are sensitive to counters should be fine, but those with extreme sensitivities should still be a little cautious. I have been able to run sockless in my pair, however did get some Achilles chaffing. With socks this is not a problem at all, but those looking to run without socks (triathletes) should get their feet used to this. Overall the upper is secure, snug and comfortable, making it a great choice for a variety of distances.

I always size up 1/2 size in the Endorphin line because I find my regular size too short. I am normally a 9.5 in non-Endorphin Saucony shoes, and Saucony sent me a 10 in the Endorphin Pro 3. This gives me a full thumb's width between my big toe and the front of the shoe. The toe box is wider than average and allows a very mild amount of toe splay. The heel counter is quite flexible and accommodating, with only a small central piece that has some structure to it. The heel collar is lightly padded and overall very comfortable, although I did have a couple of runs where I had some rubbing of the upper part of the heel collar on my Achilles. I did not experience this issue after dialing in the laces. The mesh upper is very comfortable and does not stretch. The upper provides excellent lockdown without a need for a heel lock. The mesh is a little rough internally, so I do not think it would be comfortable to run sockless in this shoe. The tongue is thin, partially gusseted, minimally padded, and has three large holes in it for ventilation and weight savings. I did not have any issues with tongue slippage or irritation and overall did not notice the upper at all while running (except for the couple instances of Achilles irritation as mentioned above). The laces have some texture to them and have plenty of length for proper lockdown. Overall, the upper of the 3 feels slightly higher volume than the 2. I found the fit of the 3 more comfortable than the 2 as well. This may be due to the different material in the upper of the 2 and 3 - the upper of the 2 is softer and has a little less structure than the 3. The mesh of the 3 feels like it sits away from the foot slightly, which may reduce the likelihood of hot spots. I find the 3 to be the best fitting Endorphin Pro yet.


Matt: The Endorphin Pro 3 is a super foam, max stack height, carbon fiber plated racing shoe that can handle racing from the 5k to the marathon. The newest version is lighter, softer, bouncier, taller and faster than previous. A new maxed-out stack height of 39.5 mm /31.5 mm of PWRRUN PB creates a much softer and bouncier ride than before. This provides a far more responsive ride that is both responsive and rolling. This is not the same firmer ride as the Endorphin Pro 1 or 2. It is not mushy either; the Speed Roll feels particularly efficient but is integrated well with the foam to provide a comfortable and efficient ride. There is a solid heel bevel in the rearfoot that is slightly lateral. This provides a smooth transition at heel strike and the foam compresses nicely underfoot. There is an 8mm heel drop that feels comfortable to me. It might be a little higher or lower depending on where you land due to the higher and softer foam. The forefoot is particularly fast and smooth at toe-off. The Speed Roll provides a quick transition due to the solid forefoot rocker, but the toes are in a fairly neutral position.

There are strategically placed outsole pieces of XT-900 that have held up well. The outsole only has minor abrasion in my normal posterior lateral section on my left foot. After 30 miles of hard running, it is still only minor and I have yet to do any significant damage. The large amount of PWRRUN PB has remained consistently bouncy, if not more so as the shoe has broken in. For that reason, the Endorphin Pro 3 will last as long if not longer than most lightweight trainers as opposed to most racing shoes.

The Endorphin Pro 3 feels like a completely different shoe than the Pro 1 and 2. The lower weight is noticeable at 7.2 oz / 6.2 oz (men's size 9/women's size 8) and the responsive midsole make it extremely fun to run quickly in. The large amount of softer foam and inherently stable ride also make it great for longer distance efforts, including long uptempo runs at marathon effort and even warm-ups/cool-downs. I have used this shoe for short 400s, longer intervals, tempo runs and even during the second half of a long run. It has excelled during all of these, but does particularly well during longer intervals, tempo runs and marathon efforts. While some people may prefer a little less shoe for 5k and below, the Endorphin Pro 3 will be a 5k to marathon racer for a large population of people.

I had a lot of fun testing the Endorphin Pro 3. I have used it for long runs and intervals ranging from 800m pace to marathon pace. While it definitely felt like too much shoe for 800m pace, it performed exceptionally well at all of the paces I tested it at. It was particularly enjoyable for a 30 min tempo run at marathon pace, where I really appreciated the bounce and roll that the high stack PWRRUNPB and Speed Roll provide. It is amazing what a difference an extra 4mm of foam can have on the ride of a shoe. The Endorphin Pro 1 and 2 have a firmer ride, which always prevented me from considering them as a marathon racer. The 3 has a bounce that is not quite as soft as Vaporfly or Alphafly, but is a significant improvement from versions 1 and 2. At initial contact, the shoe responds immediately with a bounce, followed by the familiar forward rolling sensation of the Speed Roll. At marathon pace, it is a very pleasant ride and one that feels like it would keep your legs fresher through 26.2 miles. At faster paces, it becomes more responsive, but does not lose that bounce sensation. Like versions 1 and 2, the shoe has an 8mm drop. As a midfoot striker, it feels like less drop to me, similar to the feel of the 1 and 2. At 6.2 oz for a women's size 8, the Pro 3 is a very light shoe and feels very light on foot. This shoe could be a racer for 5k through marathon, depending on the individual runner.

The amount of rubber coverage of the outsole has improved from previous versions. I found the traction on wet roads to be above average and better than versions 1 and 2. I have 50 miles on my pair and there is the faintest amount of wear at the lateral midfoot and under the great toe. I would expect good durability from the Endorphin Pro 3, also similar to the 1 and 2.


Matt: The Saucony Endorphin Pro 3 is a neutral shoe, but has several methods that make it a solid stable neutral racer. There are now sidewalls in the midfoot on both the medial and lateral sides. This provides a guided transition through that area. The midfoot outsole also has been widened and does not narrow significantly, providing inherent stability. There is also some slight lateral bias there, as the medial outsole extends more than the lateral outsole at the midfoot (the lateral side comes up, while the medial side stays in full contact with the ground). In typical Saucony fashion, there is a large amount of sole flare. The heel has a solid amount, providing a centered ride with the slightly posterior lateral heel bevel. The forefoot has the most, particularly at the lateral side to keep people guided forward. This plus the speed roll, forefoot/rearfoot guidance lines and plate make for an efficient and guided transition forward. The Saucony Endorphin Pro 3 will certainly work for those with neutral mechanics, but with the inherent guidance, will easily work for those who need mild stability. This shoe excels especially on longer faster runs when your mechanics break down, so it is an excellent marathon shoe for the above reasons. Those with moderate stability needs will certainly be able to use this for shorter, faster and maybe even moderate distances with training, but may also want to consider the Saucony Tempus (REVIEW).

The Endorphin Pro 3 is a neutral shoe with some non-traditional stability features. The highly rockered sole provides an exceptional amount of guidance from initial contact to push-off. The heel bevel and early toe spring encourage forward motion, regardless of where initial contact occurs. There is moderate sole flare throughout the length of the shoe, again helping to center the foot as it progresses through stance phase. There are also guidance lines in the midsole in the rearfoot and forefoot, which may also help with a smoother, more centered transition. 


The Impact of 4MM
By Contributor Andrea Myers

The most noticeable change in the Endorphin Pro 3 is the additional 4mm of stack height. This has completely changed the ride of the shoe, giving it the bounce that runners have become accustomed to in other super shoes. Why does such a small additional amount of foam have such a large impact on performance?

The simplest explanation is that shoes with a higher stack height increase the runner's functional leg length. Research has found that if body mass is maintained, an increased leg length due to a higher stack shoe will increase running economy (Steudel-Numbers et al 2007). Another study of elite Kenyan distance runners found a significant relationship between leg length and running economy (Mooses et al 2015). This may be because increasing stride length may be a more efficient strategy to increase speed as compared to increasing cadence (Muniz-Pardos et al 2021).

Additionally, a higher stack shoe provides additional spring space for loading and energy return. A defining feature of super shoes is a lighter weight midsole foam that has higher energy return than EVA or PU. A 2018 study done by Wouter Hoogkamer and colleagues compared three shoes: a Nike prototype similar to the Vaporfly (PEBA/ZoomX) was found to have 87% energy return, the Adios Boost 2 (TPU) had 75.9% energy return, and 65.5% for the Nike Streak 6 (EVA). The Nike prototype shoe had a stack of 31mm/21mm, the Adios Boost 2 was 23/13mm, and the Nike Streak 6 was 23mm/15mm (Hoogkamer et al 2018). The lighter weight of foams like ZoomX and PWRRUNPB allow shoe companies to use more foam without negatively affecting the weight of a shoe.

The advantage of a higher stack shoe is significant enough that World Athletics released a rule in 2020 stating that the thickness of a marathon shoe must not exceed 40mm. It is no surprise that Saucony chose to increase the stack height of the Endorphin Pro 3 to just under the 40mm limit.


Steudel-Numbers KL, Weaver TD, Wall-Scheffler CM. The evolution of human running: effects of changes in lower-limb length on locomotor economy. 
J Hum Evol. 2007;53(2):191-196.

Mooses M, Mooses K, Haile DW, Durussel J, Kaasik P, Pitsiladis YP. Dissociation between running economy and running performance in elite Kenyan distance runners. 
J Sports Sci. 2015;33(2):136-144.

Muniz-Pardos B, Sutehall S, Angeloudis K, Guppy FM, Bosch A, Pitsiladis Y. Recent Improvements in Marathon Run Times Are Likely Technological, Not Physiological. 
Sports Med. 2021;51(3):371-378.

Hoogkamer W, Kipp S, Frank JH, Farina EM, Luo G, Kram R. A Comparison of the Energetic Cost of Running in Marathon Racing Shoes [published correction appears in Sports Med. 2017 Dec 16;:]. 
Sports Med. 2018;48(4):1009-1019. 


Matt: This has been my go-to workout shoe from the moment it arrived and will be my race day shoe of choice. This is everything I always wanted the Pro series to be. It has the bounce that makes it extremely responsive and comfortable over a variety of distances. The upper is breathable, snug but still stretches for comfort. There is a small heel counter but it is not obtrusive. AND it is the inherent guidance that works for me both during faster efforts as well as warm-ups and cool-downs. My only suggestion is to consider widening up the toe box just a little for longer efforts, but I have not had any issues due to the mildly stretchy mesh.

Saucony keeps improving the Endorphin Pro line, and the 3 is the best yet due to the additional stack and updated upper. My main recommendation would be to standardize the sizing between the Endorphin line and all other Saucony shoes, as many runners have to go up a half size in the Endorphin line. I would also love to see Saucony enter the 5k/10k market with a lower drop, plated racing shoe. 


Matt: The Saucony Endorphin Pro 3 is an elite-level super shoe for racing from the 5k to the marathon. It is softer and far bouncier than the previous versions, combining both an efficient roll with high responsiveness. The upper fits far more secure, with a super light mesh and a racing-style fit that still has some wiggle room. Several methods of new-age guidance provide an inherently stable ride that will work for a larger variety of people than previous and support you during longer races when your mechanics start to fall apart. With enough comfortable cushion to be used as a marathon shoe and enough speed to be used down to the 5k, Saucony truly has a winner with the newest version of the Endorphin Pro series. 

The Endorphin Pro 3 is a high-performance racing super shoe for runners with neutral mechanics. The Speed Roll technology provides an exceptionally smooth ride and may reduce work at the 1st MTP and ankle. Runners who found versions 1 and 2 to be too firm will be very pleasantly surprised by the improved ride of the 3. The 3 has more than enough bounce to be used as a marathon racer and is responsive enough to be used in races down to 5k. 


Fit: A- (Snug fit with light breathable mesh. Secure while still being light, although toe box does taper a bit, which may make the shoe feel short for some. Feels true to size for me.)
A (Max stack height, efficient, highly bouncy and fast ride for 5k-marathon races and workouts)
Stability: A- [BorderlineStable Neutral] (Excellent stable neutral shoe with sidewalls, filled in midfoot, well placed sole flare. Sole still softer)
DPT/Footwear Science: A (Awesome evolution of the shoe, from the bounciness/responsiveness to the inherent guidance. A true super shoe that will challenge the best out there. Excellent integration of a newer methods of guidance without being obtrusive, while still making an incredibly fast racing shoe)
Personal: A (My go-to workout/race shoe and current racing shoe of the year. Comfortable, fast, bouncy and inherently stable for my mechanics)
Overall: A

Fit: A- (many runners need to go up 1/2 size, otherwise fit and lockdown are exceptional)
Performance: A 
(higher stack gives the shoe bounce in addition to roll, performs well at a variety of paces, could be used for racing 5k-marathon)
Stability: B+ (neutral shoe with some non-traditional stability features, provides guidance without forcing motion)
DPT/Footwear Science: A (additional 4mm of stack has greatly improved the ride and performance of the shoe)
Personal: A (my favorite Endorphin Pro yet due to increased bounce, could be a potential marathon racer)


Price: $225 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 Saucony 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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