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Saucony Endorphin Speed 4 Review: Traction Town
By Matthew Klein and David Salas

Born from research that reported that different people responded best to different levels of stiffness, the Saucony Endorphin Speed series has been an incredibly popular line. From a daily training shoe to a racing shoe, people have used it for all kinds of purposes. This earned the shoe a reputation as being a do it all model that could handle training and racing. Version 3 seemed to depart from the series a bit, turning a little less aggressive and more trainer-like. Version 4 redirects that course, increasing in aggressiveness and returning the series to a more workout/racer purpose. Those who have loved this series should not fear as it now feels like a cross between Versions 2 and 3. How exactly that feels... read on to find out. 


Saucony Endorphin Speed 4
Price: $169.95 at Running Warehouse
Weight: 8.2 oz, 233 g (men's size 9), 7.2 oz, 206g (women's size 8)
Stack Height: 36 mm / 28 mm
Drop: 8 mm
Shoe Purpose: Nylon Plated, Super Performance Trainer/Racer

Pros: Fast versatile ride that handles long runs and fast runs equally well
Cons: Heel a little clunky at first 

The Saucony Endorphin Speed 4 is a nylon plated super shoe capable of everything from long runs to workouts and races. Building on this versatile series, Version 4 combines the comfort of Version 3 with the speed of Version 2. The result is a more aggressive ride and fit that pushes this shoe a bit more into the workout/race realm of this series. The full-length PWRRUN PB midsole and nylon plate remain with an updated geometry that makes for a slightly more stable heel and a smoother forefoot transition. A new upper provides a slightly more snug fit, best for those with normal width feet wanting a relatively secure lock down. Best for those who want a shoe that can do a bit of everything, the Saucony Endorphin Speed 4 returns faster than ever, cementing itself as more of a racing shoe this time around. 

: Puma Deviate Nitro 2, Topo Athletic Specter, ASICS Magic Speed 3
PAST MODEL: Saucony Endorphin Speed 3


Matt: The Saucony Endorphin Speed 4 fits me true-to-size in my normal US men's size 10. The fit has a tiny bit more length than the prior version (which fit me a tiny bit short). The volume is still slightly low and I have noticed a little pressure on the top of my fifth toe. However, I had have no issues even over 14 mile long runs. The upper is light with good breathability. The forefoot is normal to slightly snug. The midfoot fits normal with a thinner gusseted tongue. The heel fits normal to a tiny bit wide and I had to lock the laces down (but not lace lock) to ensure a secure fit. There is somewhat flexible heel counter in the rearfoot with mild heel collar padding. Those sensitive to collars may have some issues but I did not. I would highly suggest socks with this shoe as the posterior part of the tongue is a bit scratchy. Some people may be able to get away with this, but I will still encourage socks. The reinforcements in the upper and slightly lower volume make this shoe secure up front with a need for some slight lace tightening from a little extra width in the rear of the shoe.

David: The Saucony Endorphin Speed 4 fits true-to-size in my Men's 9.5. The engineered mesh is surprisingly comfortable and plush for how lightweight it is. The dimensions of the fit are dialed in pretty well. The width of the heel is normal to slightly narrow, the midfoot normal, and the forefoot slightly wide. The volume is slightly lower than normal and does give an aspect of a snug fit throughout the shoe. The lacing system and tongue are done well and do provide a good balance of comfort and lockdown. The tongue is gusseted. Though it is thin, it provides a surprising amount of plushness and airiness. The heel does have an internal heel counter with mild padding. The calcaneus (heel bone) sits in a little deeper with a bucket like hold due to some sidewalls integrated around the calcaneus and the shallow heel counter. The experience is a pretty nice hold on the foot. The length of the shoe might be a tad long but I had no issues with slippage or translation of the foot. From a fit standpoint, this is my favorite Endorphin Speed.

Doctors of Running Checklist

Is This a Good Shoe for Walking: No
Is This a Good Shoe for Standing:
Is the Forefoot Flexible: Mild flexibility due to nylon plate
How Flexible is the Shoe: On the stiff end of the spectrum, but does have mild flexibility in the forefoot
Is This a Good Heel Bevel: Centered
Recommended for Haglunds:
Recommended for Sockless: No
Durability Expectation: Above Average


Matt: The Saucony Endorphin Speed 4 is a slightly more flexible super shoe/super performance trainer. It continues to feature a full-length PWRRUN PB (PEBA) with a nylon winged plate. While version 3 was the most relaxed of the series, Version 4 turns that around. I immediately found this shoe better for workouts and uptempo runs. It does have the versatility for easier efforts, especially during long runs. However, I found other shoes more appropriate for relaxed shorter to moderate pace efforts.

The midsole feels like a true PEBA midsole with plenty of bounce. The weight is plenty light to be considered a lightweight trainer but the ability to pick up the pace makes this easily accessible as a racing shoe as well. There is an 8mm drop although it feels a tiny bit higher. There is a large, centered heel bevel but the rearfoot features a large amount of medial and lateral flare. This makes the heel feel a little large and clunky at first. This transitions into an incredibly smooth midfoot and forefoot, which effortlessly roll forward. The forefoot transition does not feel like a traditional stiff super shoe but still feels snappy. I finally figured out that I had to actively load the heel to use this shoe best, which provided a guided ride at heel strike. The transition makes this shoe smooth enough for longer efforts and this has been my go-to long-run shoe for weeks. It easily moves between easier paces and faster runs as many of those long runs had 3-mile tempos at the end (while pushing a stroller). I have also enjoyed this as a primary workout shoe and used it for tempo runs, intervals, hill repeats and uptempo efforts. It has shined during all of those and I have put down similar times to other super shoes.

Durability-wise this shoe has been excellent. I have 102 miles on my pair and although there is wear, the heel is still intact. I ripped through the prior version and it was no longer usable after 100 miles for me (for those new to DOR, I am extremely hard on shoes) but this version still has plenty of mileage left at this time. For that reason, this shoe will last longer than others in its category. While the durability is still good, I would keep this shoe to road surfaces. The exposed plate area is a risk for rocks getting stuck. The traction is really great, especially in the forefoot. I have used these on plenty of wet and slippery road runs without issue. So those going into wet pavement runs should be plenty confident with the outsole of this shoe. 

David: I was very happy with the performance of the Endorphin Speed 4. The 3 did not work very well for me, but many updates make the 4 better for me. One thing I noticed immediately was the underfoot traction. It is very grippy and almost has a lattice like construction to it. I have found that I can turn on the track really well in these, run in single track (not super technical footing), and hit turns without much issue. The rubber and design feels stickier to the ground and was an immediate improvement for me. The geometry is also well balanced. The shoe has a mild to moderate heel bevel and toe spring, though it does not come off as being overly rockered. I have found that I can both ease into jogging and turn over quite quickly in this shoe with decent comfort with both.

I will say my calves do seem to work a small amount more when running faster, though this is welcomed on the track on a flatter geometry. For longer runs though, it might be nice to have a tad more rounding up front. The heel fit does seem to give a good sense of hold and stability due to the sole flaring and bucket sensation. There are some mild guidance features in the shoe that make you feel a little more centered as well. I have taken this shoe through a variety of pacing. Everything from easy miles to mile race pace feels relatively doable in this shoe. This is definitely a training companion/workout shoe I will keep around. It is good see the Endorphin Speed get some of the versatility back. 



Matt: The Saucony Endorphin Speed 4 is a neutral shoe but has some features that help with heel guidance. There is a solid amount of sole flare medially and laterally at the heel that make for a centered, albeit initially clunky landing until the shoe breaks in. There are large sidewalls with wings of the plate extending out both directions in the midfoot. The forefoot is on the wider end sole-wise which combined with the good forefoot rocker provides a quick transition forward. The above make for a guided heel landing. The midfoot does narrow a little, which combined with the softer sole has caused me some midfoot fatigue with longer miles. This is fine with shorter miles but is another reason this shoe leans a bit more neutral than the last version. It is still on the verge of being stable neutral but will certainly not get in the way of those who are sensitive to stabilizing methods thanks especially to the softer midsole. 

David:  The Saucony Endorphin Speed 4 is definitely a neutral shoe but does have some things that help with stability. The shoe does seem to have another wide version of the Nylon plate that extends the width of the midsole. This is integrated really well with the sidewalls both medially and laterally in the forefoot. As mentioned earlier the heel does have a nice hold to it as well. The heel counter and shallow sidewall wrap from the midsole does give a good sense of security. The outsole traction is really good and the best of any Endorphin Speed so far. The running experience does feel more grounded and versatile than previous versions. The upper security is pretty good throughout as well and I did not have any major translation or slippage issues. The PWRRUN PB does have an element of softness to it and the platform still has a very neutral feel to it overall. 

Endorphin Speed 3 vs. 4
Thoughts as a DPT: Should You Train In PEBA Shoes?
By Matthew Klein

When PEBA-based shoes first came out, I was quick to caution that this footwear type should be kept for faster and race efforts. This came from concerns about our lack of knowledge regarding how our bodies respond to these shoes types and the transition back to normal trainers. We now know that these shoe types can reduce the sensations of delayed onset muscle soreness, improve efficiency, may cause stiffer landing mechanics (due to the softer soles), can shift load upwards away from the ankle to the hip and knee but can also overwork the ankle in the case of instability (Agresta et al., 2022). Thanks to some great research from Justin Matties, we also know that people who train in super shoes tend to get faster in them with less muscle soreness, but tend to improve their efficiency more in traditional footwear (Matties et al., 2023).

Some of these things were more concerning before PEBA and super foams started to be integrated into training shoes. Now that this foam is more common, it is less about the foam type and is back to what the purpose of the shoe is and who it may be designed for. People have been using the Endorphin Speed series as lightweight trainers, racing shoes and more since its debut. The Endorphin Speed 4 will be no different, although its increased aggressiveness does put it more into the faster/racing end of that spectrum. That said, the fact that it has a bit more flexibility may be helpful at a greater variety of paces, even down to slower ones, compared to carbon-plated super shoes (Ortega et al., 2021). We have early evidence that many classic super shoes do not seem to benefit slower runners as much as faster runners (Joubert et al., 2022). How that effects safety and injury rates is not known.

Therefore, with the prevalence of the foams, if you find PEBA shoes help you stay healthy and enjoy running, then by all means train in them. From a performance standpoint, it does make sense to keep these for faster workouts/long runs/races as they were designed while getting your basic miles in more traditional shoes. What that balance looks like will be unique to each person. Shoes are tools and should be used as they are intended for the best results. 


Agresta, C., Giacomazzi, C., Harrast, M., & Zendler, J. (2022). Running Injury Paradigms and Their Influence on Footwear Design Features and Runner Assessment Methods: A Focused Review to Advance Evidence-Based Practice for Running Medicine Clinicians. Frontiers in Sports and Active Living4, 815675

Joubert, D., Dominy, T., & Burns, G. (2022). Effects of a Highly Cushioned Racing Shoe on Running Economy at Slower Running Speeds. SportRxiv

Matties, J. R., & Rowley, K. M. (2023). A pilot study: effects of an 8-week training intervention in carbon-plated running shoes. Footwear Science15(sup1), S182-S183.

Ortega, J. A., Healey, L. A., Swinnen, W., & Hoogkamer, W. (2021). Energetics and biomechanics of running footwear with increased longitudinal bending stiffness: a narrative review. Sports Medicine51(5), 873-894.


Matt: The Saucony Endorphin Speed 4 is a great update that adds back some of the speed that left a bit with Version 3. My only suggestions center around the heel. While this does break in somewhat with time, I might taper the medial and lateral sole flare just a little to reduce the slightly clunky (relative for a super shoe) rearfoot. This would also be accomplished with a posterior lateral bevel instead of a centered one. I get the split heel design and the implementation of a separate lateral crash pad. I still think a posterior lateral bevel would be better, although it cannot be extreme due to the amount of compression the midsole foam can go through. Outside of that, this is a fantastic update that lends itself back toward its name. 

David: This is my favorite Endorphin Speed. I think if I had to make any changes though I would make the toe spring just a tad sharper. Though I love it for running fast, I do find my calves working a tiny bit harder than normal. This is great on the track, but I'm thinking more along the lines of sensations 15+ miles into an effort. It would be nice to have a small amount of roll added to the forefoot. 


Matt: Yes. I would definitely recommend the Endorphin Speed 4, especially for those who have not responded to super shoes with extremely stiff rides. The increase in relative flexibility from the nylon plate makes this shoe a far more accessible option to many people. I think this will take the place of the New Balance Fuelcell SC Elite v3 as the people's racer. The upper provides a racing style fit while still being comfortable enough for easier and longer efforts. This shoe works best as a long run, workout and race shoe for those who don't like stiff shoes. It's increased aggressiveness makes me hesitate to suggest it for easier runs. Those who used the Endorphin Speed 3 for easier run purposes may find a slightly different shoe in that regard. 

David: I would. This is definitely a do it all shoe that you can log daily miles, workouts, and even races in if you want to. The increased traction and well balanced profile makes for a very versatile experience. Though there is some rounding, this is not a super rockered shoe. Those wanting a less dramatic rocker shoe for some training or speed work will like this one. Traction is also really good.


Fit: B+/A- (Secure forefoot with a little extra heel room that requires lockdown)
A- (Responsive, fast shoe that easily handles longer runs. Versatility that leans toward faster and longer efforts)
Stability: B+ [Neutral] (Guided heel with more neutral midfoot/forefoot)
Cost to Performance: A- (Durable super racer/performance trainer with high level of versaility)
Personal: A- (My go-to long run shoe. The slightly more flexible forefoot makes this shoe comfortable at a huge variety of paces)
Overall Design: A- 

Fit: A- (Dimensions are really good, though length a tad long)
Performance: A- 
(Very versatile, very responsive, very fun. I would like to have a tad more of a rolling sensation in the forefoot though)
Stability: B+/A- (Traction underfoot is really good, upper lockdown is solid, Peba and platform feel very neutral, wider plate noticeable and heel hold is good)
Value: A (I think you'll get your money's worth out of this one)
Personal: A (Could be in consideration for tempo/workout shoe of the year)
Overall Design: A- (Very fun yet balanced construction)


Saucony Endorphin Speed 4
Price: $169.95 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, Santa Barbara, Danbury and Stevens Point areas, we 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 pairs.  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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Mizuno Wave Rebellion Flash 2

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