Our verdict

The Endorphin Speed 3 from Saucony is one hell of a shoe! We affirm that it's energetic, stable, and light; it ticks all the important boxes of a tempo running shoe. Even more, it can be your do-it-all trainer. From easy days down to the faster, more competitive race days, we are able to count on this Saucony trainer.

Pros

  • Peppy all the way
  • Comfy for easy days
  • More stable than ever
  • Cushioned for long miles
  • Quick and smooth transitions
  • Lightweight
  • Airy as hell
  • Roomy toe box
  • Fit is amazing
  • Grippy on dry and wet roads

Cons

  • Rubs the heel
  • Not for narrow feet
  • No reflective details

Audience verdict

89
Great!

Who should buy

Definitely grab a pair now if you want a: 

  • fast shoe with loads of kick for both speed training and race days,
  • running shoe that's also cushy and stable for daily runs and long miles.

The Endorphin Speed 3 is a one-stop shop that can take you from a daily workout to a race!

Saucony Endorphin Speed 3 profile photo

Who should NOT buy

Everything about the Saucony Speed 3 gets a thumbs up from us, save for the heel counter. It's less padded, which is slightly abrasive to the heel. You can stock up on the bandaid or consider Saucony Kinvara 14.

However, if you're head over heels in love with the Saucony Endorphin series but want a comfier heel wrap, it's best to stick with the Saucony Endorphin Speed 2. It's also a great alternative for those with slim feet.

Saucony Endorphin Speed 3 lab view

Breathability

From double-layer mesh to single-layer mesh, this speedster is airy AF. If you plan to use it in the summer, we have nothing else to say, but lace it up! 

This Saucony shoe gets a solid 4 out of 5 for breathability based on our lab tests and on-road experience.

Test results
Endorphin Speed 3 4
Average 3.8
Compared to 209 running shoes
Number of shoes
1
Breathability
5

Durability

Outsole hardness

As a speed-oriented shoe, it is expected that the Endorphin Speed 3 cuts corners on the outsole's durability.

Not only do we see less rubber at the bottom, but we also found it to be softer than average with he help of a durometer.

Saucony Endorphin Speed 3 outsole hardness

If you don't mind sacrificing 0.6 oz of weight in return for a sturdier outsole, we can highly recommend the ASICS Novablast 3 speed trainer.

Test results
Endorphin Speed 3 77.0 HC
Average 80.3 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 260 running shoes
Number of shoes
55.5 HC
Outsole hardness
92.8 HC

Outsole thickness

The rubber is not only softer, it is also thinner in this Saucony shoe. Our caliper shows only 2 mm of rubber which is a millimeter thinner than average.

Saucony Endorphin Speed 3 outsole thickness

Test results
Endorphin Speed 3 2.0 mm
Average 3.2 mm
Compared to 279 running shoes
Number of shoes
0.0 mm
Outsole thickness
6.6 mm

Weight

On average, speed trainers weigh in at 248 grams/8.7 ounces.

But the Endorphin Speed 3 beats that by weighing only 212 grams/ 7.5 ounces! This is exceptionally light given how much cushioning this Saucony shoe has!

Saucony Endorphin Speed 3 scale

Test results
Endorphin Speed 3 7.94 oz (225g)
Average 9.35 oz (265g)
Compared to 280 running shoes
Number of shoes
5.26 oz (149g)
Weight
12.56 oz (356g)

Cushioning

Heel stack

With the amount of cushioning that it packs, the Saucony Endorphin Speed 3 is a mile eater. And a very good one too! 

Saucony Endorphin Speed 3 heel stack height

Even though our caliper shows an average amount of stack height (34.1 mm in the heel), it definitely feels like plenty on the run.

Important note: the brand advertised slightly different numbers. The shoe is supposed to have 36 mm for the heel stack height.

Test results
Endorphin Speed 3 34.1 mm
Average 33.5 mm
Compared to 279 running shoes
Number of shoes
7.6 mm
Heel stack
42.7 mm

Forefoot stack

As for the forefoot stack, our caliper returned 26.7 mm which is over 2 mm thicker than average!

However, it is a little less than the officially stated 28 mm.

Saucony Endorphin Speed 3 forefoot stack height

Test results
Endorphin Speed 3 26.7 mm
Average 24.9 mm
Compared to 279 running shoes
Number of shoes
7.6 mm
Forefoot stack
35.8 mm

Drop

At 7.4 mm, we found the shoe's heel-to-toe drop to be close to the official specs (8 mm). This is a middle-of-the-pack drop that works great for both beginner and seasoned runners.

Saucony Endorphin Speed 3 drop

Test results
Endorphin Speed 3 7.4 mm
Average 8.6 mm
Compared to 279 running shoes
Number of shoes
-0.8 mm
Drop
16.1 mm

Insole thickness

Measuring the shoe's insole, we found it to be slightly thinner than average at 3.6 mm. But this is still quite padded for a speed trainer - no need to be concerned with underfoot comfort.

Saucony Endorphin Speed 3 insole

Test results
Endorphin Speed 3 3.6 mm
Average 4.4 mm
Compared to 275 running shoes
Number of shoes
1.5 mm
Insole thickness
7.3 mm

Midsole softness

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.

The Endorphin Speed 3 also gets comfier than its predecessor. There is a gentle give in the shoe's midsole and it works better for easy days too!

Turning to our durometer, we found that the shoe's foam is in fact in the top 10% of the softest in our lab!

Saucony Endorphin Speed 3 midsole softness

With a reading of 13.8 HA, the Endorohin Speed 3 is on par with shoes like ASICS Novablast 3 (13.5 HA) and the PUMA Deviate Nitro Elite 2 (13.9 HA).

Test results
Endorphin Speed 3 13.8 HA
Average 21.3 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 207 running shoes
Number of shoes
8.5 HA
Midsole softness (soft to firm)
41.5 HA

Difference in midsole softness in cold

It was incredible to find out that the Endorphin Speed 3 remains soft even after 20 minutes in the freezer!

At room temperature, our durometer showed 13.8 HA and after the freezer, it only firmed up by 5%(!) becoming 14.5 HA.

Saucony Endorphin Speed 3 freezer

Even after being exposed to the cold, the shoe remained 65% softer than other shoes at room temperature.

Test results
Endorphin Speed 3 5.1%
Average 25.7%
Compared to 206 running shoes
Number of shoes
0%
Difference in midsole softness in cold
100%

Ride

This time around, the Endorphin Speed 3 comes back with more bounce and a snappier toe-off which makes picking up the pace so easy!

Saucony Endorphin Speed 3 run trails

The shoe lives up to our high expectations left by the previous Speed 2.

And this is not just because it's a shoe that has speed written all over it. It's also because the nylon plate it has (responsible for the snappy toe-off) doesn't feel harsh. Compared to other plated running shoes, the Endorphin Speed 3 is more natural-feeling.

At the same time, the shoe hasn't lost its bounce either. So you can still push the pace and go as fast as you want.

Saucony Endorphin Speed 3 mid run

What's more, in this iteration, the shoe's Speedroll rocker geometry is very noticeable. Each step feels as if the foot is carried forward. Love it!

Stability

Lateral stability test

This Saucony shoe doesn't feel very stable and it's not supposed to. As a speed trainer, its primary task is to keep you on your toes as you smash that interval training or chase that new personal best.

There is not much stability to lean on when you decide to slow down.

Torsional rigidity

Another detractor from the shoe's stability is its high level of torsional flex.

Performing a manual test, we rated the Endorphin Speed 3 with only 2 out of 5 for torsional rigidity. That puts the shoe on the more flexible side of the spectrum.

Test results
Endorphin Speed 3 2
Average 3.2
Compared to 258 running shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

The heel could use a little more padding.

This is the ONLY complaint we have for the Saucony Endorphin Speed 3. The shoe's heel is a tad bit uncomfortable and scratchy because it has minimal padding.

Saucony Endorphin Speed 3 heel area

This is definitely due to the choice of materials because the heel counter itself is very soft, it scored 2/5 on our flexibility tests (5 being the stiffest). 

Their recommendation? Wearing thicker socks is a must. As well as carrying a couple of bandaids.

Test results
Endorphin Speed 3 2
Average 2.7
Compared to 242 running shoes
Number of shoes
1
Heel counter stiffness
5

Midsole width in the forefoot

We also found that the Endorphin Speed 3 runs slightly narrow in its platform.

The widest part of the forefoot turns out to be 111.5 mm, 1.5 mm narrower than average. But the good news is that it's not so critical and the brand did its homework to improve the 3rd iteration.

Saucony Endorphin Speed 3 midsole width forefoot

Test results
Endorphin Speed 3 111.5 mm
Average 113.5 mm
Compared to 280 running shoes
Number of shoes
100.5 mm
Midsole width in the forefoot
126.5 mm

Midsole width in the heel

The Speed 3 is proof that Saucony really listens to runners' feedback. In the past, the Endorphin Speed's weak point was its lack of heel stability.

Saucony Endorphin Speed 3 width midsole heel

But this model changes all this. Based on our caliper measurements, the shoe's base has been widened by 5 mm in the heel.

Test results
Endorphin Speed 3 89.5 mm
Average 90.3 mm
Compared to 280 running shoes
Number of shoes
74.9 mm
Midsole width in the heel
106.6 mm

Flexibility

Stiffness

As our manual flexibility test shows, the Endorphin Speed 3 is on the flexible side. But let's see what the controlled lab measurement shows us.

In this test, we bend the shoe to a 90-degree angle and use a gauge to measure how much force it takes to do that.

Turns out, this Saucony shoe only needs 23.5N! This is 30% less than it takes a road shoe on average. This also proves that the nylon plate embedded into the shoe's sole is more forgiving than a carbon plate.

Test results
Endorphin Speed 3 23.5N
Average 29.4N
We use an average of four tests. The video shows one of those tests.
Compared to 262 running shoes
Number of shoes
2.2N
Stiffness
94.4N

Grip / Traction

The outsole has plenty of traction and plenty of durability too! We felt safe at all times, even on wet asphalt passages. And during fast corners, the grip doesn't compromise. 

Saucony Endorphin Speed 3 outsole

Size and fit

Toebox width at the widest part

Even though the Speed 3 is only average in the widest part of the forefoot (98.5 mm), it feels roomier because of the stretchy nature of its fabric. The latter makes the shoe feel much more accommodating in the toebox.

Saucony Endorphin Speed 3 toebox width

We believe that Saucony absolutely nailed the fit of the Endorphin Speed 3! The upper does a really great job mimicking the natural shape of the foot. 

Saucony Endorphin Speed 3 profile

Test results
Endorphin Speed 3 98.5 mm
Average 98.3 mm
Compared to 280 running shoes
Number of shoes
89.5 mm
Toebox width at the widest part
109.1 mm

Tongue: gusset type

The shoe's secure wrap is also complemented by its semi-gusseted tongue and padded laces. They work so well together; getting a solid lockdown won't be a challenge in the Speed 3.

Saucony Endorphin Speed 3 laces

Test results
Endorphin Speed 3 Both sides (semi)

Comfort

Tongue padding

There is also a moderate amount of tongue padding - 3.9 mm, based on our caliper measurement. It is 2 mm thinner than the average but is just perfect for a speed shoe. 

Saucony Endorphin Speed 3 tongue thickness

Test results
Endorphin Speed 3 3.9 mm
Average 5.6 mm
Compared to 277 running shoes
Number of shoes
0.5 mm
Tongue padding
14.2 mm

Saucony Endorphin Speed 3 vs. 2

This version of the Endorphin Speed doesn't go through a lot of changes, which is why runners continue to rave about it. It has minor touch-ups, which make it an even better version: 

  • The wider toebox and thinner, stretchier upper for a more precise fit and a breathable running experience 
  • More stability in the forefoot and heel because of the widened base 
  • A new plate for a snappier toe-off
  • Stripped-down heel padding to minimise the bulk as much as possible  

Saucony Endorphin Speed 3 soft cushion