Share He also revealed his a series of spots on his back - likely from undergoing cupping therapy. Cupping is an ancient form of alternative medicine and a detox treatment loved by many Hollywood stars, such as Justin Bieber, Gwyneth Paltrow, Kaley Cuoco and Jesinta Franklin. Working hard: Cody went shirtless as he did pull-ups while wearing a waist belt and with a weight plate in between his legs. As he showed off his muscular physique, he also revealed large marks on his back from cupping therapy The therapy is a form of acupuncture, and is based on the idea that suction from the cups draws the skin up and increases blood circulation and energy around the body.