I have been spinning now for a few weeks.  I was doing it for fitness before planning to do a triathlon.  Now there is an even bigger reason to keep up the spinning.  I have to say, I really enjoy the spin class.  It has pushed me to the limit more than any workout I have ever done.  When I train on my own I typically give up when I get tired.  Spinning in a class with all these other people, the loud music, and the great spin instructors, I feel like I can’t quit, so I press right through it.   Lots of hard work, but lots of fun.  Ultimately if I get to the point where I do an Ironman triathlon this spinning stuff will be easy in comparison.