The reference marathon shoe against the strongest claim to its crown.
The short answer
The ASICS Metaspeed Sky Tokyo is 28g lighter (170g against 198g), the ASICS Metaspeed Sky Tokyo is £45 cheaper at RRP (£240 against £285), and both hold their foam for roughly 250km of racing. Both are inside the World Athletics 40mm road limit.
Weight · men's US 9
Alphafly 3198g
Metaspeed Sky Tokyo170g
0320g
Price · UK RRP
Alphafly 3£285
Metaspeed Sky Tokyo£240
0£450
Competitive life · km before the foam fades
Alphafly 3250km
Metaspeed Sky Tokyo250km
0700km
■ marks the better figure, where better is not a matter of taste
Both soles, one drawing3 units per mm · the line is the 40mm road limit
Alphafly 340mm — on the limit
Metaspeed Sky Tokyo39.5mm — on the limit
The tape
manufacturer-stated · ■ the better figure, where better is not a matter of taste
Still the reference marathon shoe. The Air pods give a propulsive forefoot that nothing else quite replicates, and the wider platform makes it manageable late in a race when your form has gone.
■ Caution Sits at exactly 40mm — legal, but with no margin. It is a lot of shoe for anyone racing slower than about 4:30/km, and the forefoot pods reward a genuine forefoot strike.
For stride-length runners — the Sky is built to let your stride open up rather than turn over faster. Arguably the best all-round marathon shoe currently made.
■ Caution ASICS splits the line by running style. If you race by increasing cadence rather than stride length, the Edge is the correct shoe and this one will feel wrong.