" Thanks to the students’ posture exercises, their willpower didn’t get depleted as quickly as before, so they had more stamina for other tasks. You could try the two-week posture experiment to improve your own willpower, or you could try other exercises. There’s nothing magical about sitting up straight, as researchers subsequently discovered when they tested other regimens and found similar benefits. You can pick and choose from the techniques they studied, or extrapolate to create your own system. The key is to concentrate on changing a habitual behavior. "

― Roy F. Baumeister , Willpower: Rediscovering the Greatest Human Strength