I did this routine this morning with a 30# powerbell and I have to say, I can see why people spontaneously puke while doing this. It was hard and I had to buckle down to make it through. And I only did it the one time, not the suggested three times. 7 minutes and I'm done for two days. We have a wellness program at work that offers all kinds of fitness classes and one of them is a 1 hour kettlebell class. I'm going to have to sign up for them.