NBC’s American Ninja Warrior has sparked a full on fitness trend. The obstacle course that contestants battle their way through on the show is being replicated in gyms across the country so that anyone can train to be a Ninja Warrior. Some of these gyms have formed a National Ninja League to grow the sport, with Ninja competitions and championships. At the same time, the number of applicants to the show has skyrocketed, going from 5,000 at the end of season 6 to 50,000 at the end of season seven, the most recent. (Racked)
