Savannah Chrisley is burning calories without moving an inch. The 23-year-old "Chrisley Knows Best" star stripped down to just a sports bra and tie-dye sweatpants today for a little influencing on Instagram, with the blonde's 2.2 million followers seeing how you can, in Savannah's books, tone up your abs while plonked on your couch. Savannah, who fronts South Beach Diet, was promoting Body Revolution's patch-on technology, and she even filmed her vibrating abs as they worked. Check it out below.