The top portion of a running or cycling shoe is the part that overlies the top and sides of the foot. It provides support, lets air in, and helps the shoe fit comfortably.
Shoe upper materials vary—mesh for breathability, synthetic for durability, and knit for comfort. A successful shoe upper design blends strength, fit, and support. A shoe upper with a roomy toe box allows the toes to spread out further, which can prevent injury. Proper shoe upper design prevents blisters, hot spots, and fatigue during extended events.
