The best Vitamin isn't in a pill, it's on your feet...a sleek superlight sports sneaker that'll help you move more and feel great. (Here in a fun and functional version, incorporating innovative yarn that glows a dazzling green when it's dark, so you're more visible in low light/nighttime.) Biomechanically engineered for exercise and casual running, but equally good for upping your everyday activity – from speedwalking to work or cycling round town. This FFX evolution features a redesigned cleaner-look upper. In an engineered two-layer stretch knit, that combines high-breathability areas with extra support at the sides/arch. There's more padding on the collar and tongue. And a new easy-entry topline makes it simple to slip on/off. With splashproof translucent TPU detail around the sneaker that's practical when you head outside. On our Neodynamic™ midsole: light, high-rebound, impact-reducing cushioning, with a springy central carbon plate that propels you forward and smooths out movement heel to toe. Flexible yet stable, with contoured footbeds for superb arch support (and pressure diffusion). Movement-motivating magic. Note: To get them glowing these sneakers need to be 'charged up' by the sun: simply leave or wear yours in daylight. For maximum effect wear in pitch black surroundings. (The top knit layer and TPU branding on the tongue are glow-in-the-dark.) Other features: Toe spring & heel kick smooth out movement Internal 'flex grooves' help feet move naturally Midsole widens at forefoot & flares out around trainer for stability TPU heel clip helps stop foot rolling Silver reflective TPU heel strip