The stability ball is an integral part of core strengthening for personal training and group exercise workouts. Resist-A-Ball® is unlike any other program because of its comprehensive instructor education, fitness programming, DVDs and marketing support. With Resist-A-Ball®, you’ll add challenge to your clients’ workouts while improving their posture, core strength, balance and flexibility. Best of all, Resist-A-Ball® stability balls are known for their quality, strength and durability, so you’ll always be ready to roll. Take a course and get on the ball with official Resist-A-Ball® education.