Nike Alphafly 1 vs Saucony Endorphin Pro 3: Which Carbon Racer Should You Buy?

Introduction

Even though the Nike Alphafly 1 is now a slightly older carbon racing shoe, it still competes directly with the Saucony Endorphin Pro 3, and both rank among the best options on the market for racing. The real question is whether it is worth hunting down a bargain on the older Alphafly, or going straight for the newer Saucony. We have run marathons and personal bests in both, and the answer is less obvious than the price tags suggest.

Specs and Construction

On paper the two shoes differ in meaningful ways. The Endorphin Pro 3 has an eight millimeter drop, while the Alphafly 1 sits at four millimeters. Weight also favors Saucony: 217 grams (7.7 ounces) in a UK 9 versus 234 grams (8.3 ounces) for the Alphafly.

Construction follows the expected super shoe recipe on both. The Alphafly 1 uses an Atomknit upper over a ZoomX midsole, a very soft and springy PEBA-based foam, with Air Zoom pods in the forefoot and a full-length carbon plate. The outsole gets solid rubber coverage on the forefoot plus two strips at the heel, with a thick front layer to improve durability and protect the pods. The Endorphin Pro 3 has a very lightweight mesh upper, PWRRUN PB foam (Saucony’s own PEBA-based midsole), a full-length carbon plate, and Speedroll rocker geometry. Rubber coverage is decent across the forefoot and heel, and a midsole cutout keeps weight down.

Fit and Sizing

The Endorphin Pro 3 fits perfectly true to size, and one tester even ran the Chicago marathon in a brand-new pair straight out of the box with no issues. The Alphafly 1 is trickier: its raised arch caused real discomfort during the first few wears, and the shoe feels a bit tighter and less forgiving overall. True to size is still the right call, but note that going half a size down leaves your big toe bumping into a small raised plastic section at the front, so be careful if you size down.

Ride Feel: Bouncy Versus Smooth

This is where the two shoes genuinely diverge. The Alphafly 1 feels active and slightly intrusive in a good way: extremely bouncy, with a strong pop off the forefoot from the Air Zoom pods, and a sensation that it is propelling you forward with every step. One tester ran a 3:12 marathon PB in it despite never racing further than 10K in the shoe beforehand, and found it incredibly enjoyable over the full distance once an initial arch-related discomfort faded around 5K.

The Endorphin Pro 3 feels noticeably different. It does not have that obvious bounce, but it feels more natural on the run, with four of five recent PBs set in the shoe. The defining characteristic is how smooth the Speedroll technology makes each stride. It also feels lighter and more nimble than the Alphafly, and it works at a wider range of paces, whereas the Alphafly almost demands you commit to cruising mode.

How Each Shoe Ages

One subtle but important difference is how the midsole changes over time. The Alphafly 1 holds its feel remarkably well; a pair with around 300K on it feels similar to a brand-new shoe. The Endorphin Pro 3 softens up noticeably, becoming a bit mushy after roughly 140 to 200K, and a fresh pair felt firmer and better for hard running. Neither change seems to affect performance much, but some runners would actually prefer to race in a new Pro 3 rather than a broken-in one.

Which One for Race Day?

For pure racing, the Alphafly 1 edges ahead for one of us, largely because of that energetic, propulsive ride, while the Endorphin Pro 3 is the more accessible shoe that will work for more people. The Alphafly’s intrusiveness means some runners simply do not get on with it; one tester even abandoned it before a planned marathon because it nagged his calves, despite a 2:29 marathon PB previously run in the shoe. If you have unlimited choice and limited knowledge of what suits you, the Pro 3 is the safer recommendation. The Pro 3 also doubles as a superb relaxed long-run and training shoe, arguably the most forgiving super shoe if your marathon day goes badly.

Value and Availability

At list price, the Alphafly 1 costs £270 in the UK or $275 in the US, while the Endorphin Pro 3 comes in at £210 or $225. In practice the Alphafly is now widely discounted in sales, which changes the calculus considerably, though as an older model it is not always easy to find in your size. If you can land a genuinely good deal on the Alphafly, it remains a top-tier racing pick; otherwise the Pro 3 is the easier recommendation at full price.

Conclusion

Both shoes are excellent, but they suit different runners. The Saucony Endorphin Pro 3 is the best all-rounder: smoother, lighter on the foot, more natural at any pace, and easier to live with. The Nike Alphafly 1 is the more explosive race-day weapon with better shape retention over its life, and at sale prices it represents real value. Pick the Alphafly if you want maximum race-day pop and can handle a less forgiving fit; pick the Pro 3 if you want one carbon shoe that does nearly everything well.