Using these burst resistant, stability balls, simple movements become strategic as your body activates nearly every muscle to maintain balance. Target your core muscles ? abdominals, shoulders, arms, chest, lower back, butt and hips so you get lean from the inside out! Not only can you get flab-free abs, shrink your waistline and re-shape your hips using these balls; you’ll have fun doing it! Incorporate the balls into your Pilates, yoga, stability training or fitness exercises to focus on major muscles groups for maximum results. Use them to improve your body? Core strength and natural balance while getting trim and toned. The balls are especially perfect for strengthening your core stretch sand maintaining flexibility and can even be used as a desk chair or taken to the gym. Made from high density polymer that resists tearing and puncturing, the balls are designed to support up to 600 pounds of pressure. Included with your purchase is a free pump.