The Nike Alphafly 4 and the Asics Metaspeed Sky Tokyo are each brand’s carbon marathon shoe. Nike returns after almost three years of waiting with an Alphafly that again aims for the number-one spot. Asics updates the Metaspeed Sky, whose Paris version, which we tested, already offered propulsion that was hard to match.
On the scale, the Asics is lighter, by about 30 g / 1.1 oz. The Nike’s drop is a bit higher, while the Asics stays low.
Nike combines two foams, the new, lighter ZoomX LT on top of ZoomX, with a widened Flyplate and two redesigned Air Zoom units under the forefoot. Asics places its carbon plate higher in the midsole and pairs it, on this Tokyo version, with a new, softer FF Leap foam on top of FF Turbo+.
On the run, the Alphafly 4 feels balanced and slightly plush, with very strong forward propulsion and a roll that stays smooth late in the race thanks to the mechanical feel of the Air Zoom units.
The Metaspeed Sky relies on an aggressive rocker and very strong bounce, more vertical than horizontal, that lengthens your stride. At impact, the Paris version swung between plush and firm, something the Tokyo softens with its new foam. Both remain demanding, the Alphafly 4 a bit less so (it’s among the least demanding in its category).
The Alphafly 4’s widened base and plate give it stability fully on par with the competition. The Metaspeed Sky’s platform isn’t especially wide. Its precise fit, fairly dense foam and grippy outsole still give it comparable stability.
On the Nike, the Atomknit upper is light and very breathable. It doesn’t squeeze the foot, and the midfoot cables provide precise lockdown. The Paris version’s Motion Wrap upper sat close to the foot, with excellent lockdown, and some runners already found it narrow: the Tokyo tightens it further.
Traction is very good on both, including on wet roads: Fast Shot rubber on the Nike, AsicsGrip on the Asics.
Lifespan helps decide between them: the Metaspeed Sky holds up well over time, while the Alphafly 4’s foam shows wear quickly and its Air Zoom units remain a point to watch.
Alphafly 4 vs Metaspeed Sky Tokyo: Which Should You Choose?
Pick the Nike Alphafly 4 if you want a carbon-plated shoe that is more forgiving, whatever the distance.
The Metaspeed Sky Tokyo is our recommendation for fast runners who already have solid experience with carbon-plated shoes: its performance level and better durability make it an obvious choice.
