I've been hooping almost every day since about mid-November 2013. In the last few weeks, I've noticed I haven't been getting the results that I was before (even with adding more time). So today I tried something different: I hooped on my mini-trampoline. Of course, I wasn't able to bounce very high; in fact, I was only able to do the "health bounce" and hoop at the same time. That worked for my dominant hoop-spinning direction. When I switched and went the other direction, I did interval workouts of hooping while moving around the trampoline and hooping while doing high knees (well, not very high--more like "low knees"). Now after this workout I can feel the tiredness--both from hooping and from the trampoline. I imagine the energy required to keep your balance while standing on a trampoline and hooping is good exercise for your core, and it's probably intensified when you move around. Anyway, I wanted to share my experience for those who might find that hooping, though still a much beloved exercise, is not as effective as it once was.