The Download: inside an AI gym, and how to make the internet safer

Chloe, an energetic young coach, promises to help you crush your fitness goals. The disciplined Rex, who has the air of a drill sergeant, encourages his clients to strive for excellence, but he is quick to warn that there won't be any shortcuts. If you're after a more mellow approach, Emma and Ethan are warm and quietly confident. But Lumin Fitness is no ordinary gym. These trainers don't exist--at least not physically.