Time Out says
No, the nudists aren't taking over Grant Park. Instead, Naked Juice is partnering with CorePower Yoga for a free, hour-long yoga class in the park from 12pm-1pm. Attendees can stick around to sample some juice and play games. You'll get a reusable tote, a t-shirt and a frisbee for your trouble and the first 125 participants will receive a free yoga mat.