“I’m a fierce believer in children’s ability to pull on their boots and go outside on their own,” says Fredrika Mårtensson, the environmental psychologist who conducted the study. “There’s an enormous difference between walking and getting a ride somewhere. I believe you have to let transportation take its time in order to gain appreciation for the way the world works. It doesn’t necessarily have to be a scenic walk. Nature is everywhere when you’re outside, even just the wind blowing in your face.”