“Katy Milkman played tennis at Princeton, and when she finished college, she went to the gym every day. But when she started grad school, her fitness routine went south. ‘At the end of a long day of classes, I was exhausted,’ Milkman says. ‘Frankly, the last thing I wanted to do was drag myself to the gym. What I really wanted to do was watch TV or read Harry Potter.’ But Milkman, who went on to study human behavior and decision-making, found a way to have her exercise and her Harry Potter, too: She resolved to only indulge her love of fantasy novels at the gym — listening to audio books through earbuds. The pairing did the trick. ‘I started out working out again regularly,’ she says, thanks to the young wizard and other fictional series, like The Hunger Games, Alex Cross mysteries, all the vampire novels. Milkman is now a professor at the Wharton School of Business, and her research applies ideas from economics and psychology to nudge people into good habits. Researchers like her may have insight into quirky human foibles, but they’re human, too. So how do they stick to good habits, like exercise, saving money or eating well? ‘We might be worse at it than other people,’ Milkman says. ‘Yes, we’re better than we were before we started studying it, but we started out far worse than the average candidate.’ Read more on NPR.