The NOVABLAST® 4 running shoe features a new midsole and outsole geometry that helps produce an energized ride. A tongue wing construction in the upper helps improve the fit while reducing tongue movement. It's complemented with an engineered woven upper that offers more stretch, ventilation, and durability. FF BLAST™ PLUS ECO cushioning is made with 20% recycled bio-based content. This material helps create softer landings and a more energized toe-off during your training.