Petting your dog before you leave home is a must. Researchers at the University of Pisa have found that if you pet your dog one last time before you head out the door, it'll reduce anxiety for your pup and for you. They say it takes just five minutes of petting to lower cortisol, the stress hormone, and boost oxytocin, the feel-good hormone, for owners. As for the doggos, their heart rate goes down and they become more relaxed. The scientists say a win-win for a dog and his pet parent.