RiRi knows how to rock a bikini any time of the year (and on any stage)! The 24-year-old singer is known for posting some of her sexiest pics ever on Instagram, so this sneak peek of her Barbados campaign that she tweeted on December 26 comes as no surprise. But getting her taut and tight tummy takes work; she’s trained with fitness expert Ary Nuñez for the past four years. “We focus on the core muscles, and we do a ton of repetitions,” Nuñez told SHAPE. “Rihanna is so connected to her body. She used to work out because it was part of her responsibility, but now she works out because she loves it!”
