Exercise ball Exercise ball An exercise ball, also known as a Swiss Ball, is a ball constructed of soft elastic with a diameter of approximately 35 to 85 centimeters (14 to 34 inches) and filled with air. The air pressure is changed by removing a valve stem and either filling with air or letting the ball deflate. It is most often used in physical therapy, athletic training and exercise. It can also be used for weight training. The ball, while often referred to as a Swiss ball, is also known by a number of different names, including balance ball, birth ball, body
Ball-and-pillow structures paper called "Ball or Pillow-form Structures in Sandstones." Here he referred to these deformations as pillow-forms or ball structures. The actual term "ball-and-pillow" came from Potter and Pettijohn (1963), when they cited Smith's work incorrectly. Ball-and-pillow structures Ball-and-pillow structures are masses of clastic sediment that take the form of isolated pillows or protruding ball structures. These soft-sediment deformations are usually found at the base of sandstone beds that are interbedded with mudstone. It is also possible to find ball-and-pillows in limestone beds that overlie shale, but it's less common. They are normally hemispherical or kidney shaped, and range in size