An exercise ball, also known as a stability ball or Swiss ball, is a large, inflatable sphere used for physical fitness and rehabilitation. Typically made of durable rubber, it comes in various sizes to accommodate different heights and exercises. The ball can improve balance, core strength, and flexibility when used in workouts or physical therapy. Using an exercise ball can enhance traditional exercises, such as sit-ups and push-ups, by adding instability, which engages more muscles. It is also popular in yoga and pilates routines. Many people use it as an alternative to a chair for better posture and to strengthen their back muscles.