Invented in New York in the 1940s, Pilates brings together elements of yoga and stretching, weight-based training and ancient Roman calisthenics. Many practitioners compare it to a jerky form of yoga, although it tends to be much more intense and cardiovascular. It is popular among many groups, including professional athletes, those recovering from physical trauma and pregnant women. Advanced Pilates classes involve equipment, but beginners should only need mats. Pilates is not as well-known or as popular as yoga in Berlin, and there is only a handful of certified teachers.