Only tried them on for 10km. Official Description: A shoe that pursues speed. The Nike Vaporfly 3 allows you to run at a speed worthy of race day, no matter the distance. It's made for chasers, racers, and pacesetters with an unyielding spirit of exploration. This iconic model from the super shoe series has been remade and its engine tuned. You can aim for a personal best in a 10km run or a marathon. This versatile road racing shoe is recommended for both elite runners and race beginners. It's perfect for runners who believe speed is necessary to run longer distances and reach seemingly unattainable heights.