Saucony Endorphin Pro 3 vs Nike Alphafly 2: Two Top Carbon Racing Shoes Compared

Introduction

The Saucony Endorphin Pro 3 and Nike Alphafly 2 are two of the strongest carbon plate racing shoes of their generation, and both earned serious mileage in marathon training and racing. They share an 8mm drop but take very different approaches to speed: the Alphafly 2 is big, spongy, and propulsive, while the Endorphin Pro 3 is smoother, lighter, and more nimble. Here is how they compare across fit, ride, racing, and value.

Price and Weight

The Alphafly 2 is the more expensive shoe at £270 in the UK and $275 in the US. The Endorphin Pro 3 comes in at £210 in the UK and $225 in the US, a meaningful saving. The Alphafly 2 is also the heavier shoe at 244 grams (8.6 oz) in a UK size 9, while the Endorphin Pro 3 weighs 217 grams (7.7 oz). Both are true to size.

Design and Build

The Endorphin Pro 3 uses a lightweight mesh upper with plenty of holes for breathability, plus a tongue with large ventilation openings. There is a little cushioning at the back but not much, as expected in a racing shoe. The midsole uses PWRRUN PB foam, a PEBA-based compound with a full-length carbon plate, and Saucony’s Speedroll geometry creates a nice rocking effect on the run. Rubber coverage is decent at the forefoot and heel, with midsole cutouts to reduce weight.

The Alphafly 2 features Atomknit 2.0, a structured one-piece bootie-style knit upper with a fairly significant heel counter to add stability. Its midsole is mostly ZoomX foam, Nike’s PEBA-based foam, with Air Zoom Pods at the forefoot for a firmer, poppier feel and more ZoomX foam running underneath the pods. It is a wide shoe built with stability in mind, has a very significant midsole cutout that almost amounts to a decoupled midsole, and the outsole has good forefoot coverage plus two strips at the heel for grip without extra weight.

Fit and Comfort

Both shoes are true to size. The Endorphin Pro 3 gave no problems with foot movement on the run. The Alphafly 2 is a bit harder to get on at first, but two pull tabs help, and once your foot is in, the bootie construction holds it very securely. One caveat on the Alphafly: be careful about sizing too close to the front of the toe box, because the way the rubber curls up can cause big toe issues if you go half a size down.

Ride Feel: Bouncy Tanker vs Smooth Sports Car

These two have very different rides. The Alphafly 2 is a lot more noticeable: a big, spongy, bouncy, propulsive shoe, like pulling a luxury car onto your foot and settling into cruise mode straight away, yet it can still move very fast. The Endorphin Pro 3 is much smoother with a bit of bounce, keeping you ticking over with its Speedroll geometry and plate for an almost effortless feeling ride, like you are kissing the ground and not slowing down as you run long.

The Alphafly 2 gives you force back with every stride, while the Pro 3 simply helps you along. Both are fast at any distance, but the Pro 3 feels noticeably more nimble, and the Alphafly rewards locking into a pace and staying there.

Short Races and Speedwork

In short races and track-style reps, the lighter Endorphin Pro 3 makes it easier to pick up your feet and push toward the end of a 5K or 10K. In one direct comparison session, the Pro 3 felt remarkably agile and nimble during an all-out parkrun, locking it in as a top-tier carbon shoe, and dropping back to marathon pace afterward felt great. The Alphafly 2 cruises brilliantly at marathon pace and was surprisingly good in a 5 mile race and a 10K race, both run in high-mileage weeks, but it can feel like you lock into a pace rather than kicking hard for home.

Long Runs and Marathon Racing

The Endorphin Pro 3 was the preferred long run shoe, more comfortable and protective over a 20 miler and a hard 24 miler, purring along and holding pace nicely. The Alphafly 2, however, tips you forward and keeps you going when you are truly struggling late in a long run or race; it helps you stay locked into target pace even with very tight legs. Both are excellent marathon shoes, and the Alphafly 2 tilts more toward longer events while the Pro 3 is the more versatile option on the track and over shorter distances.

Durability and Stability

The Alphafly 2 felt basically the same after 150k, with its big bouncy ride unchanged. The Endorphin Pro 3 began to soften after around 100-120k; the ride became more comfortable, though for all-out pace the firmer feel of a fresh pair was preferred. On stability, the Alphafly 2 is more stable than past versions thanks to its wider base, which reduces the pinching feeling under the arch some people experienced with the first version, though a little remains. The Endorphin Pro 3 has a more natural feel and no major stability elements, but it is naturally quite stable.

Which One Should You Buy?

The Endorphin Pro 3 is the easier recommendation for most people: it is cheaper, works well across a range of distances, holds up in training, and its natural rolling feel suits more runners straight away. The Alphafly 2 remains a fantastic choice if you want maximum comfort and extra help at the end of a hard marathon, and it even sits under the 40mm stack limit despite pushing the limits in size and looks. If price and versatility matter most, go Endorphin Pro 3; if you want the most propulsive marathon shoe available and budget is no issue, the Alphafly 2 delivers.

Conclusion

Both are genuinely excellent carbon racing shoes with plenty of overlap, and you would likely enjoy either. The Endorphin Pro 3 wins on price, versatility, and nimble short-distance performance, while the Alphafly 2 stands out for long-distance racing comfort and late-run propulsion.