I have read a few articles that say indoor ex bike riding won't make you fit. Indoor Cycling Probably Won't Make You Fit. Here's Why.. I realize that the bike must be combined with some sort of weight training especially upper body and core. I think your lower body gets quite a workout already. They offer a ton of strengthening classes by the way. I ask you if the Peloton won't make you fit what will? I can't do treadmill because of my bad knee. The Peloton classes do not bother my knee. I just find this kind of talk frustrating.