ZoomX Invincible Run Flyknit
Most of that comfort comes from the ZoomX midsole made from Nike’s top-tier Pebax-based foam. It’s among the lightest, plushest, and most responsive around, and has the capacity to return about 70 percent of energy with each footstrike, the most of any material we’ve tested at the RW Shoe Lab. ZoomX delivers exceptional bounce and bottomless softness, without packing out or feeling overly mushy, and the Infinite Run has more of it underfoot than any other daily trainer in Swoosh’s lineup. To keep the Invincible Run riding smoothly atop all that foam, the sole uses a slightly curved rocker while a horseshoe-shaped heel counter holds the back of your foot steady on touchdown. Nike also widened the forefoot and flared the foam around the heel to further stabilize landings. Still, testers said the shoe felt a bit wobbly on tight corners and crowned roads or buckled sidewalks. That said, the expanded forefoot did have one very noticeable benefit—the fit felt more accommodating to runners who had experienced cramped toes in the narrower Peg 38.