Gymnic Stability Ball Plus   Product Price: $26.95 Quantity: Select Size 45 cm (18") - Green (Priced at $26.95) 55 cm (22") - Green (Priced at $29.95) 65 cm (26") - Green (Priced at $34.95) 75 cm (30") - Green (Priced at $39.95)       Gymnic Plus Stability Balls are constructed of latex-free vinyl material in four different diameters from 45 to 75cm (18 to 30 inches). Benefits/Uses Increases muscle strength Improves proprioception, balance and stability Helps develop the core body muscles by forcing the body to respond to the the instability of the ball. Can be used in place of a chair to help maintain proper posture as it engages the abdominal and back muscles. Develops strength in all planes of motion (frontal, sagittal, and transverse) which helps improve overall functional strength and decreases the chance of injury. * Holds up to 600 lbs static weight. Features 2 Year Warranty Holds up to 600 lbs. PUMP NOT INCLUDED Available in four sizes. These are suggested sizes: (You should select ball size where you can sit with knees bent at a 90 degree angle) Up to 5'0" tall use 45cm; 5'1" to 5'7" use 55cm; 5'8" to 6' use 65cm; Over 6' use 75cm Exercise sheet by Juan Carlos Santana includes 40 exercises for body alignment, balance, abdominal strength as well as chest, back, shoulder, leg and hip strength. View the Stability Ball Exercise Video ASK THE EXPERT - JUAN CARLOS SANTANA, M.Ed., CSCS Director of Institute of Human Performance in Boca Raton, Florida 1) What is the right size stability ball? If you were to only get one size I would recommend the size that allows you to sit on the ball and keep a 90 degree bend at the knees and hips. However, many exercises require different size Stability Balls in order to provide the proper intensity. An example of this is an abdominal stretch while lying on the ball: A bigger ball provides a more gentle stretch than a smaller ball. 2) Is a deflated ball more or less stable? Although a deflated ball has more surface area contact with the ground, it is less stable due to the slow reaction forces with the body surface (e.g. the hands). When a ball is deflated, it is hard to find and maintain the center of mass under the body’s base of support, thus making it hard to balance. 3) Does one develop stability or balance when using the ball? Exercises requiring less force develop balance, while exercises requiring more force develop stability. Stability is by far the most important component to develop with the stability ball. For more information, training articles and exercises visit the Stability Ball Training Zone. Don't forget exercise bands to use with your stability ball! Shop for Exercise Bands and Tubing. Related Products PB Elite Molded Foam Rollers $24.95   Blaster Hand Pump $12.95   BOSU Balance Trainer $119.95