After a few reps at the gym your muscles naturally start to fatigue. It’s a sign that you’re working and your muscles are responding. In the same way that your muscles eventually give out during a workout, your mental muscle starts to fatigue throughout the day, hampering your ability to care, make choices, stay motivated, weigh decisions, and ultimately take action. Radishes and chocolate chip cookies can help us understand why. In 1998, Roy Baumeister and colleagues asked people to sign up for what participants thought was a taste-perception experiment. The researchers formed three groups: radish eaters, chocolate-chip cookie eaters and