The Pilates Reformer was designed by Joseph Pilates and is the most popular of all the Pilates apparatus. It works on a spring tension system with a moving bed. Exercises can be done in many positions; lying down, sitting, standing, in four point kneeling and side lying to name a few. Resistance is added by pulling the straps, pushing the footbar, balancing and in all different positions. It is fantastic for alignment and proprioception (being aware where your body is in space) as it uses a grid like system with your hands and feet in contact with either the apparatus or the straps. It can make exercises more challenging or can aid them. It opens a whole new vocabulary of Pilates exercises.