The motivational phrases beloved of sportspeople might seem trite, but for players from Katie Boulter and Andy Murray to Arthur Ashe, they’re surprisingly important “These are simple refocusing strategies,” says Professor Ian Maynard, a sports psychologist at Sheffield Hallam University. “Most athletes constantly worry about winning or losing, but all they can control is performance. These triggers are designed to bring them back into themselves rather than worrying about the enormity of the situation.” Jens Voigt, the retired German cyclist famed for his endurance, trademarked his inspirational slogan. “Shut up legs” has appeared on countless handlebars since. If Murray progresses…