North Avenue Beach (1600 N. Lake Shore Dr.) is the site of what might best be described as a health and fitness free-for-all this Saturday, with half-hour workouts (kicking off at 10 AM with “buff yoga,” which incorporates strength training, and wrapping up with a Caribbean dance workout at 4:20 PM), beauty and spa treatments, golf-swing lessons, and rock-wall climbing. There’ll also be a fashion show, live reggae band and a DJ, foosball, air hockey, and–that godsend to retailers of fitness everywhere–free beer. If you’re in the mood for more punishment after happy hour, a mechanical bull and something called the “treadmill challenge” will be running all day. Click here for more info.