Time Out says
If you love switching up your workout routine, an aerial fitness class could be just what you're looking for. With locations in River North, Lincoln Park and South Loop, AIR is a core-strengthening, giggle-inducing, downright tough workout. The class utilizes long, colorful silks that hang from the ceiling, allowing you get upside down and propel yourself up toward the ceiling. It's just as fun as it looks, but be forewarned: You'll be sore the next day.