Here's an idea for a sequel to The Shallows: Blake Lively is once again hiding from a terrifying predator who will rack her body with pain. This time, it's not a bloodthirsty shark. It's a personal trainer with visions of burpees and side planks dancing in his head. Run, girl!If you photoshop in a seagull and a rash guard, Lively's latest Instagram looks like it came straight from a film set. The actress, who recently gave birth to her and Ryan Reynolds' second daughter , is playfully hiding under some gym equipment. Meanwhile, her personal trainer, Don Saladino, lurks menacingly next to her."#FitnessFriday current mood," she captioned the pic. "@donsaladino gives me [a] reason to hide!"