Gene Simmons has boldly claimed that artists like Beyoncé, Bono, Mick Jagger and Bruno Mars wouldn’t be able to perform in his famously over-the-top costumes, due to their excessive weight and unwieldiness.In an extensive new interview with Entertainment Tonight, the KISS frontman explained that, especially at age 72 – more than 50 years since he first debuted with the band – fitness is crucial to maintaining his prowess as a performer. “We work hard at it,” Simmons assured journalist Kevin Frazier, telling him the band currently enjoy “no drugs, no booze, no smoking.