Reducer: Thomas Denson, a psychologist at the University of New South Wales, found that we can increase self-control in the same way we strengthen weak muscles—literally. For two weeks, right-handed volunteers had to use their left hand to do just about everything: brush teeth, open doors and stir the milk in their coffee. Later, these self-made lefties were less likely to retaliate when provoked than people who hadn’t been forced to switch hands. The surprising lesson here is that tiny tweaks in bodily self-control can have such an impact on anger management. “They rely on the same circuitry,” Denson says. Other exercises that require self-discipline may work just as well—like constantly keeping your shoulders back, spine straight, and chin up.