Mariah Carey stunned her fans by doing exercises in heels at her age. Many praised the star and admired her physique, citing that she is in “great shape.” International music icon Mariah Carey, 54, amazed her Lambs (the name of her fanbase) in a recent video she posted to her Instagram account. As a way of teasing and poking fun at the fact that many know her for being a fabulous diva, Carey showed herself all dolled up while doing activities. What piqued fans’ interest was that she was doing a workout in high heels. Not only was she rocking heels while exercising on a leg weight machine, but …