As a "gym bro" that exercises every day and eats healthy (I'm not a bodybuilder, but I have a good body) I would say that our demographics is more republican, but not in a sense that we're conservative of opposing abortion, same-sex marriage etc… we're liberal in that sense, is more of an "anti-woke" sentiment
Yeah there's the culture war stuff, there's also a huge emphasis on individual responsibility in gym culture, and you don't need me t tell you which side of politics is better at messaging that.