The arms in fact act to set the tempo in running while also stabilizing and thus have a direct effect on running technique. Freedom of movement is therefore crucial for performance.
Frictionless freedom of movement
Flexibility of the Expansion Flex Zone and the stretch of the yarn enable unrestricted movement. In addition, the Stretch Ribs allow a problem-free riding position in the shoulder area without pulling up the shirt. That guarantees all of the different technology stays where it belongs to optimally achieve its intended function.