Speed Skaters 'Run' On Ice, So Why Do Their Arms Go Sideways?


Speed skaters swing their arms backward and to the side, not back and forth. Why?As the skater pushes off the ice with his back foot, a force is exerted on the skate blade in a right angle.The only way to propel yourself forward is to push off the ice in a diagonal motion, rather than straight back.If a skater tried to push off the ice in a direction parallel to the skate blade, they couldn't do it.That's because there is almost no friction between the ice and skate blade.