The Gold's Gym Stayball offers an innovative solution to the problem. The Stayball's breakthrough design keeps the ball in place, so users can safely change positions and perform various exercises without losing their balance. No more chasing the ball across the room or fumbling to complete a workout! The Stayball maintains the key function of an exercise ball: engaging core muscles with its dynamic surface. Using the Stayball strengthens the core muscles, the source of good posture, balance, and stability. The Stayball comes with everything you need to get rolling (without actually rolling an inch): a dual-action hand pump for easy inflation, a workout DVD with two 30-minute workouts and an exercise chart to teach proper form. The same revolutionary innovation that keeps the StayBall in place also allows consumers to use the ball as a 5-pound weight. Used as a weight, the StayBall provides added resistance and increased calorie-burn to even the simplest exercise.