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
Lost ball warrens, molehills or the like, or where there is a tree in the field of play and no local rule about what happens when it is hit. Previously 'lost ball' could only be called when the ball could not be found. This has resulted in some ridiculous local games where batsmen scored a large number of runs whilst the fielding side fetched a ladder to climb up a tree the ball had got lodged in. (The ball not being lost as it was readily visible.) The current version of the Law prevents this, as now 'lost ball' can also be