OMG, I have never in my life experienced a harder work out, and it was only a 30 minute demonstration class. The classes teach people how to dangle themselves from silk scarves hanging from the ceiling like acrobats. A club I am a member of set up a 30-minute lass to give Air Chicago a try. For 30 minutes our teacher provided a demonstration of their classes and we all tried to follow along. I hear our class was a combination of the more experienced classes, to give us a taste of what we can work up to, but fortunately, if you begin taking classes here, although they are 50 minutes long you start off slow, and work your way up to the more advanced things we did today. I was impressed at how much my classmates and I were able to complete within just 30 minutes of trying to dangle ourselves from silk scarves hung from the ceiling. Overall, a tough workout, but so much fun, I may have to sign up to do this again. And guys, our class was about half men and women, and the men had a great time and found it to be a huge challenge as well.