Abstract: Gymnastic apparatus designed to strengthen the muscles of the abdomen at waist level, those located in the small of the back and in the buttocks and to exercise and maintain all of the rest of the body's muscles, including a base, a bar which can be moved in any direction, one of whose ends is fitted with a sleeve, and whose other end is connected to the base by means of a connection mechanism.The connection mechanism includes a ball holding the end of the bar which is housed in a tube whose upper end is shaped to match the upper end of the ball, with the lower end of the tube being secured to the base. Said ball can move in all directions in response to movement imparted to the ball, within a space limited by the upper end of the tube and by a part forming a seat for the ball mounted on the base by means of an adjustment mechanism making it possible to adjust friction of the ball.