How good was the sunset tonight!!! Gotta love group training with a view like that. Our Funk HiiT session are the best way to lose fat while keeping your muscle shape. Over 10 stations, we keep heart rate at 70% for 35mins. OPOC, stands for "excess post-exercise oxygen consumption" informally know as the afterburner effect. This afterburn effect will boost the calorie burn, long after you have finished training.