Alphafly 4 vs Alphafly 3: Is the Upgrade Worth It?

The Alphafly 3 was the shoe to beat for two years. The Alphafly 4 doesn't change the formula, it polishes it. If you already own a pair of 3s, the question is whether the polish is worth about $280. If you own neither, it's whether the newer shoe is worth more than a 3 on sale.

What changed underfoot. The 4 adds a layer of ZoomX LT, a lighter version of Nike's race foam, above the carbon Flyplate, with standard ZoomX still below it. The plate is wider, and the Air Zoom pods are now heat-welded instead of glued, which makes them softer and almost silent. The 3's Air pods are the source of its famous squeak.

The numbers. Nike lists the 4 at about 208 g in a men's US 10, roughly 10 g lighter than the 3's 218 g. Stack drops by a millimetre to 39 mm at the heel and 31 mm at the forefoot, keeping the same 8 mm drop. Nike says it's 5% lighter with 10% more energy return, both from its own lab. Independent scales broadly agree on the weight saving, though exact figures vary by size.

How they run. Both are bouncy, propulsive marathon shoes that work best for a midfoot or forefoot strike at steady race pace. The difference is the platform. The 3's narrow midfoot made some runners feel tippy, especially late in a race. The 4's wider base and forefoot make landing anywhere on the shoe easier, and the ride rolls through more smoothly. The 3 still feels slightly more raw and aggressive, which some runners prefer.

Fit and upper. The 4 gets a new Atomknit upper that holds the midfoot a little better. Both run true to size and narrow in the toe box, so try them on if you have wide feet.

Price. The 4 is around $280, slightly cheaper than the 3's $285 launch price. With the 4 on shelves, expect the 3 to drop well below that, which is where it becomes a real bargain.

Our verdict: if the Alphafly 3 felt unstable or you're buying your first Alphafly, get the 4. It's the better shoe in every way that matters. If the 3 already suits you and still has life in it, there's no rush to upgrade. Use your current pair for this race season and buy a 4 when the foam is done.