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Saucony Endorphin Pro 2 Review
Written by Chief Founder Matt Klein and Contributor Nathan Brown

The Saucony Endorphin Pro is one of only two carbon plate shoes out on the market with peer reviewed literature behind them. Jared Ward participated in a study that looked at what the optimal plate and sole stiffness was for each person. Fun fact: it varies depending on the person. The original Endorphin Pro was also one of the first shoes outside of the Nike Vaporfly to use a Peba foam and carbon plate combination. It differed though in that it was more of a roller than a bouncer. The introduction of the Speed Roll made the shoe incredibly smooth and a great, efficient choice for 10k to marathon racing. The Saucony Endorphin Pro 2 returns with some subtle upper updates. The security of the upper has improved without sacrificing that lightweight feel that many people love. Continuing to be a shoe that rolls along, those that like an efficient ride will continue to be pleased. 

Specifications for the Saucony Endorphin Pro 2 (per Running Warehouse)
Weight: 7.5 oz / 213 g (men's size 9)  6.3 oz / 163 g (women's size 8)
Stack Height: 35.5 mm / 27. 5 mm
Drop: 8 mm
Classification: Carbon Fiber Plated Distance Racing Shoe


The Saucony Endorphin Pro 2 returns with upper updates to create a more secure ride in the heel and midfoot. The S-shaped carbon plate, Speed Roll and PWRRUN PB continue on, keeping the efficient and rolling ride going. The upper continues to have a great deal of breathability with slightly more reinforced material throughout the length of the foot, particularly at the heel and midfoot. This provides a much better fit and lockdown through the midfoot in particularly, keeping the foot on the platform even with sharp turns. Best for 10k to marathon racing for most people, the continued roll and increased upper security will keep you going for miles. 


Matt: The Saucony Endorphin Pro 2 fits true to size in my normal men's size 10. The fit is fairly normal for a racer, but slightly snug throughout. The midfoot in particular fits more snug thanks to additional reinforcements through the laces. This snugs down the forefoot slightly compared to the previous version, providing a more race like fit. There is technically a heel counter, but it is so flexible that it almost doesn't count. Those sensitive to heel counters will have absolutely no problem here. The heel fits slightly more snug and is more secure than the last version. I still have not had to lace lock this shoe, but anyone doing races with quick turns may want to consider it. The tongue is gusseted and is locked in place very well. This provides additional security in the midfoot with an additional wrap over the foot. The material on the inside is comfortable. I have run a few miles sockless in this shoe and not had any issue. There is a mild toe guard that has not caused any problems. The mesh is very airy and dries fairly quickly. So those looking for a triathlon race shoe may also be happy here.

Nathan: The primary update for the Endorphin Pro 2 is the upper and fit, and there are some mild noticeable changes. But before we get to those, let's do a general description. The Pro 2 upper is a single layer and thin mesh upper that is quite snug, yet accommodating, from the heel to midfoot and stays somewhat narrow to the forefoot. However, like the rest of the Endorphin series, there is a nice amount of volume in the toe box, making it accommodate relatively nicely. Length wise it fits very true to size in my men's size 9. The big notable updates were all focused on improving the heel lock, which for me were very effective. In the original pro, I had a hard time lacing well enough to get a full lock and always had some minor slippage (actually just to the originals back out last weekend to test again and noticed the same thing). The Pro 2 narrows the heel a bit and improves the lacing system. The new lacing has slightly offcenter construction and thicker/more elastic laces, allowing to tie down tighter without irritation to the top of the foot. Overall, just a more race ready and secure fit, while maintaining a lot of breathability. 


Matt: The Saucony Endorphin Pro 2 has a ride that is identical to the first version. The PWRRUN PB foam has some bounce to it, but most of the magic happens with the Speed Roll technology combining the toe spring and the S-shaped plate. The Pro 2 is an efficient roller. Long consistent efforts are what this shoe does best. There is a heel bevel which combined with the PWRRUN PB provides a quick transition forward. The plate engages immediately and transients through the midfoot quickly. The toe spring occurs fairly early in this shoe, creating a smooth toe off. The ride is not aggressive, but the stiff forefoot is noticeable. There is an 8mm drop that not super noticeable. This is further offset by the early toe spring. This has been my workout shoe during my mild Achilles irritation and I had zero symptoms running hard in this shoe. The PWRRUN PB is engaged more during faster efforts, but as mentioned, this is more of an efficient roller. The midsole feel is fairly neutral with a slight bias towards softness due to the midsole material. It isn't firm but isn't super soft as the plate provides some rigidity.

The Saucony Endorphin Pro 2 feels best during tempo runs, long repeats and marathon pace efforts. It can certainly go down to 5k pace, but there are better shoes for that. The Pro 2 does better with longer efforts as it feels like a lightweight trainer. There is plenty of protection underfoot given the stack height and the efficient roll will keep you going for miles. Marathon pace is very comfortable in this shoe, although those not wanting as stiff of a plate will want to try the Endorphin Speed 2. This is definitely a road shoe. The traction is decent on road, but becomes a bit unstable on soft surfaces. The durability is fairly good. I have 35 miles on my pair and only see a tiny bit of wear on the posterior lateral heel. The exposed PWRRUN PB is starting to see some wear, but the blown rubber outsole has enough coverage that I do not foresee this being a problem. Given the durability of the PWRRUN PB and plate, I expect the same amount of miles for a lightweight trainer, if not more if you are light on your feet. 

Nathan: When it comes to marathon racing flats, the Endorphin Pro (1 and 2) has a distinct place. It is firmer than many of the other options, and operates most off of the geometric design (Speed Roll), plate integration, and foam to produce it's efficiency. Running in the Pro 2 does not give that overly bouncy sensation, but simply rolls along really well. The plate and foam combination is very rigid and you won't really feel much flex through the forefoot, but the rocker and toe spring makes it feel natural. I prefer this shoe for longer sustained efforts and longer races like 1/2 to full marathon compared to shorter races like 5-10K. I just actually took the Pro out on a 13 mile easy run and it felt remarkably smooth the entire way. I do think this is unique to this "super shoe": it gives a similar ride and at all paces. Other super shoes like the Metaspeed Sky, don't perform as well when I fatigue or slow up, but the Pro stays consistent even when I get tired. I particularly this this is valuable for marathon racing. 

Another notable thing about the Pro is the combination of the drop (8mm) and foam density (slightly firmer). Some of these shoes implementing such soft foams with high stack see a lot of compression through the heel. This compression effectively lowers the drop of the shoe and places more demand on the calf. I've personally experienced significant calf strains in shoes like that. However, the Pro 2 does not pose that scenario. The higher drop and firmer foam help it run truer to it's drop and maintain loading as expected. For those with calf issues, this can be a nice marathon racer option.


Matt: The Saucony Endorphin Pro 2 is a neutral distance racing shoe. There are a few elements that add stability however. In typical Saucony fashion, the sole has medial and lateral sole flare. This is most evident in the heel and forefoot. The midfoot does not have much of this and since it narrows slightly provides less stability. There are some mild sidewalls from the PWRRUN PB midsole that rise up on either side of the midfoot. This along with the S plate offsets the slight narrowing of the midfoot last as the transition through the midfoot is quite fast. The forefoot is the most stable with the sole flare, plate and significant toe spring. Those looking for a stable forefoot will enjoy this shoe. The PWRRUN PB isn't the softest foam, so when combined with the rocker and plate provide a fast transition that provides some guidance forward. 

Nathan: Compared to other neutral marathon racers in this class (Vaporfly Next%, Metaspeed Sky, etc), the Pro 2 has a bit more stability. The firmer foam, mild side walls, full contact outsole, and flaring all assist in providing a slightly stable platform throughout. It is still narrow through the midfoot in terms of outsole contact (as is expected for a races), but the rocker and smooth transitions help stabilize it throughout. 

How Rockered Shoes Can Help Unload the Achilles, by Matt Klein

Runners, particularly masters level runners (>35 years old) have a fairly high incidence of Achilles problems (Willy & Paquette, 2019). The rate of symptomatic (with pain) Achilles tendinopathy (chronic) is estimated to be about 5% in runners (Lagas et al., 2020). The rate of asymptomatic (without pain) Achilles tendinopathy in at least one tendon is estimated to be almost 50% of runners (Lieberthal et al., 2019). Given that the calf muscles, which connect into the Achilles tendon, are the primary muscles of support and propulsion in running, it makes sense this would be a common area of overuse (Hamner et al., 2010).

A shoe like the Saucony Endorphin Pro 2 has the potential to unload this area. It is well known that rockered shoes take load off the ankle, calf and Achilles tendon (Sobhani et al., 2013; Sobhani et al., 2015). Even among athletes with chronic Achilles tendinopathy, these shoe types have been known to take pressure off this area (Sobhani et al., 2015). However, in carbon plated shoes this depends highly on the stiffness and angle of the plate. The S-plate in the Endorphin Pro 1 and 2 may not be as aggressive as other shoes with full plates, which integrates very well with the toe spring (Speed Roll). This makes for a very smooth and rockered ride off the front of the shoe. It does not make for the absolute fastest ride, but certainly one of the more consistent. Anecdotally I was able to use this as my primary workout shoe during a stint with my own Achilles irritation. I had next to no symptoms except slightly during impact (which is another discussion on vibration and tendons).

In masters runners, it is well known that there can be a loss of mobility and strength at the ankle, foot and toe joints. A shoe that unloads this area and requires more work from the knee and hip (which these shoes do) may be optimal for performance. Shoes like this do shift work up to the knee and hip, which also shifts the injury risk (Sobhani et al., 2017). So while certain shoes with optimal levels of toe spring, stiffness and rockered soles may reduce load at this area, the shift in force means that smart training, adequate strength work and adequate mobility work are still required. Running is a high impact sport and requires maintenance to continue optimally. So if you are not doing the extra things for your body to maintain it, you should think about starting.

Hamner, S. R., Seth, A., & Delp, S. L. (2010). Muscle contributions to propulsion and support during running. Journal of Biomechanics43(14), 2709-2716.

Lagas, I. F., Fokkema, T., Verhaar, J. A., Bierma-Zeinstra, S. M., van Middelkoop, M., & de Vos, R. J. (2020). Incidence of Achilles tendinopathy and associated risk factors in recreational runners: A large prospective cohort study. 
Journal of Science and Medicine in Sport23(5), 448-452.

Lieberthal, K., Paterson, K. L., Cook, J., Kiss, Z., Girdwood, M., & Bradshaw, E. J. (2019). Prevalence and factors associated with asymptomatic Achilles tendon pathology in male distance runners. 
Physical Therapy in Sport39, 64-68.

Sobhani, S., Hijmans, J., van den Heuvel, E., Zwerver, J., Dekker, R., & Postema, K. (2013). Biomechanics of slow running and walking with a rocker shoe. 
Gait & Posture38(4), 998-1004.

Sobhani, S., van den Heuvel, E. R., Dekker, R., Postema, K., Kluitenberg, B., Bredeweg, S. W., & Hijmans, J. M. (2017). Biomechanics of running with rocker shoes. 
Journal of Science and Medicine in Sport20(1), 38-44.

Sobhani, S., Zwerver, J., van den Heuvel, E., Postema, K., Dekker, R., & Hijmans, J. M. (2015). Rocker shoes reduce Achilles tendon load in running and walking in patients with chronic Achilles tendinopathy. 
Journal of Science and Medicine in Sport18(2), 133-138.

Willy, R. W., & Paquette, M. R. (2019). The physiology and biomechanics of the master runner. 
Sports Medicine and Arthroscopy Review27(1), 15-21.


Matt: My major suggestion from the previous version regarding heel security was addressed very well. The heel is more locked in without using a heel counter. I did not have to lace lock the Pro 2 at all and felt stable even with turning. Great job to Saucony on this. My previous comment still stands that I think there needs to be a bit more weight differentiation between the Speed 2 and the Pro 2. The Speed 2 will continue to be a very popular shoe like the original and I think it is important that Saucony differentiate these models a little more so people have a reason to buy both. Additionally, a little weight drop may make the Pro 2 more versatile at paces below 10k for faster runners. 

Nathan: This is my current choice for Marathon Racing, and I have no major recommendations. I mentioned this in my Speed 2 review, but it might be time to differentiate the Pro from the Speed and take some risks on the next Pro design.


Matt: The Saucony Endorphin Pro 2 is for those looking for a protective, efficient ride with a secure, breathable and slightly snug fit. The heel security has been dramatically improved along with additional lock down in the midfoot. The Speed Roll, PWRRUN PB and carbon plate create a smooth ride that works great for races from 10k to the marathon. Those that like carbon plates will find plenty of cushioning here for uptempo, tempo, long intervals and marathon workouts. For runners with sensitive Achilles tendons, a unique combination of a well rockered ride, plate and lack of a significant heel counter make this shoe a great choice for speed and race days. 

Nathan: The Endorphin Pro 2 is for those looking for an efficient, smooth, slightly firmer, and rolling marathon racer. It is very protective over long miles and leaves legs feeling fresh. The 8mm drop and firmer foam lead to less calf demand compared to some other racers out there and can be a good option for those with calf/achilles issues. 


Fit: A- (Secure heel and midfoot. Forefoot slightly snug with a racing style fit.Very airy mesh with great security of heel without major heel counter)                     
Performance: A- (Speedroll is efficient and effective at running a steady pace over a long distance) 
Stability: B+ (Speedroll, sole flare and plate provide guided ride. Midfoot slightly unstable but somewhat compensated for with sidewalls and locked in upper) 
DPT/Footwear Science: A- (Very well integrated plate, toe spring that will work very well for people that need a rockered ride. This unloads the ankle/Achilles well, but Saucony needs to work on the midfoot given that instability may also contribute to Achilles issues) 
Personal:  B+ (Great longer distance racing shoe. Limited at shorter distances. Best for longer intervals, tempo runs and is among my top choices for a marathon right now) 
Overall: B+/A- (Improved upper security and a super smooth ride will make the Endorphin Pro 2 a great shoe for people looking for a long distance racer and/or a protective, efficient carbon plated race shoe)            

Fit: A (Great fit for long distance racer, thin and breathable, secure heel, purposefully narrow, but some volume in the toe box)    
Performance: A- (So consistent over long miles and keeps you feeling fresh, best for longer races, lacks top speed compared to some others) 
Stability: B+ (Firmer sole and carbon plate stabilize, but still narrow midfoot) 
DPT/Footwear Science: A (Great integration of rocker, foam, and geometry for smooth and fun ride) 
Personal:  A (My current choice for a marathon...hopefully this October) 
Overall: A  


Interested in purchasing the Saucony Endorphin Pro 2? Shop Running Warehouse here for a pair. You can also check out a pair of the original Endorphin Pro here. Purchasing from this link helps support our work at Doctors of Running. Thanks so much!

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Thanks for reading!


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 structure 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 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 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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Saucony Endorphin Speed 2 Review

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