Need some extra motivation to exercise? You might run a little faster if you were being chased by zombies. Pediatrician Dr. Sears tries a new interactive game called Zombies, Run! that combines exercise with the fear factor. “This is actually pretty cool because there’s different scenarios, different courses that make you feel you’re in a zombie apocalypse,” Dr. Sears says. “And when there are zombies behind you, you want to book it.”