Jess Hartley holds both an ACE personal training certification and a registered dietitian license, which means her clients have nowhere to hide — not in the gym and not at the dinner table. She runs an eight-week total body transformation program out of Nashville that combines periodized lifting with a flexible macro protocol, and the before-and-afters her clients post are the kind that get accused of being fake. (They're not. She makes everyone photograph their food for the first three weeks, which is the actual secret, and also the reason some clients quit.) Jess charges $3,500 for the full eight weeks and waitlists fill in under 48 hours. She's currently writing a book, which her publisher is already calling "uncomfortable" in the best possible way. But that's a story for next month.