I have followed with great interest this subject. I use a spin bike at home, the exact same as they have in the gym. It has a weighted flywheel up front that will keep going if you stop pedaling, essentially forcing you to keep up. I would imagine that there is the momentum aspect in that once you are at a certain speed it would continue but you still have to pedal. I feel great and definitely do much better when I ride. Typically I am doing about 1/2 hr to 45 mins, at 22-25mph. I does not have an rpm counter. Even if this is not what they did in the clinic I feel great and I move a lot better after riding. The bike cost about $800.00, I got it from an infomercial on tv.