Ninja (also commonly referred to as the shinobi) were mercenaries of Japan with a mysterious history. As the first written documentation of ninjas came decades after they already existed, there's debate among historians about how much of their origin story is true, and how much is legend. In this episode of Ancient Workouts with Omar, we learn more about shinobi practices from Jinichi Kawakami, the last remaining shinobi in Japan. | HISTORY

Every course comes with some splashes, crashes and straight up nose dives! Here's a look at some American Ninja Warrior epic fails. | Ninja Warrior