I'll agree that spinning helps tremendously, but I STILL don't feel I get the cardio workout in a spin session that I get outside......... maybe it's just me. Or maybe its because, as a spin instructor, I can't workout quite as hard as the class can. I HAVE to be able to have enough breathe to talk and coach. And usually, after having taught 3 classes a week, I don't have the time to go to more than one where I am a participant and can go till practically breathless. Ah well, I am very happy to hear good things about spinning. Glad you think it helps so much. And ever so glad to be able to get back outside, whether legs and lungs match or not! I'll get there soon enough........