Exercise ball standard exercises, such as a push-up, on an unstable surface can be used to increase activation of core trunk stabilizers and in turn provide increased trunk strength and greater resistance to injury. Fitness Experts and some doctors also recommend sitting on an exercise ball instead of an office chair. That is based on the theory that the abdominal and back muscles are constantly engaged and active to maintain proper posture and balance on the ball. There is no scientific evidence of those benefits occurring by just sitting without additional exercises. However, some people warn against using a Swiss ball as
Eight-ball the opponent of the fouling player wins. Most commonly of all in American – sometimes called straight eight by its aficionados, and usually played on coin-operated, smaller tables – a requirement may be that all shots be . This typically includes what balls and bank/kick cushions will be involved in the shot, and in what order. The shot considered a turn-ending (but not ball-in-hand) foul if not executed precisely as planned, but a loss of game if the "foul" shot pocketed the 8 ball. Contrariwise, some Americans hold that nothing other than the 8 ball has to be called in