Kate Hudson takes "Pilates day" very seriously. The 37-year-old actress took to Instagram on Friday to show off her expert Pilates skills -- and let's just say, she's a little more advanced than we are. "Pilates day #FableticsFriday @fabletics #BackDetail @nicolestuartla," she captioned the impressive pic, capturing how she keeps her butt toned. Hudson definitely hasn't been shy about her love for Pilates. "I'll do Tracy Anderson, I'll do Body by Simone, I do everything," the actress told Self magazine last year, before adding that she absolutely swears by Pilates. "Nothing, literally nothing, makes me feel like I'm back to my body more than pilates," she confessed. "I'll travel, and I’ll go for a run or I'll Spin. But when I go home and get on the reformer or the Cadillac, my body immediately goes back. I can see an instant shift