Reebok FloatZig X1 Trainers in white. Engineered mesh upper. Lace closure. Floatride Energy Foam. Textile lining. Rubber outsole. These Reebok running shoes help you prioritize speed during marathon training and racing. Full-length Floatride Energy foam in a Zig shape provides lightweight and responsive energy return. A full-length carbon fiber plate delivers the stiffness you need for a propulsive, energy-efficient ride.