Marathon Training Plan

Shoe rotation: NB 860 for all easy runs (4-7km, all under the ~8km mark where numbness kicks in — safe territory). Zoom Fly 6 for intervals, tempo, and roughly half the long runs — your most broken-in, proven pair (~300km). Metaspeed Sky Tokyo takes the other long runs to build mileage on it (currently only ~16km in) since you're considering racing in it. Week 9's 28km peak long run is the decision point — run it in Metaspeed, and how it holds up decides whether you race in Metaspeed or fall back to Zoom Fly for the taper long run, shakeout, and race day.