I have been riding (a road bike outside) for about 1 1/2 years. I took a spin class to see if I could learn to stand up while riding. I know some people swear by spin classes, but I found it to be awful (could have been the instructor?). It seemed to suck all the joy out of riding. Someone stood up there yelling with awful music in the background and then ordered you stand for like 10 minutes. That did feel awful on my knees. Even if I was riding outside, I would not stand that long. There was no reward or rest - like cruising down a hill. Anyway, even though I've been told it would improve my endurance, I can't force myself to do it again. Tell me what you think about it after you go.