The speed of the rotation will increase. The smooth, dynamic, non-impact nature and compact size it can be used in a fitness sense for the arms, wrists and shoulders helping to build, tone and define muscle. The Powerball (or hand held gyroscope) is a truly dynamic object, there are no batteries and no electricity used, unless you have a model with a rpm counter. The Powerball (or hand held gyroscope) is a truly dynamic object, there are no batteries and no electricity used, unless you have a model with a rpm counter. The Powerball can be used in a fitness, sports, rehabilitation or fun manner. You can even use it for fun, having competitions between friends, family or work mates to see who can get the highest score. With practice, speeds in access of 15,000 rpm's can be generated. Athletes of all levels can use the Powerball to build, tone and strengthen the muscles and ligaments in the hands, wrists, arms and shoulders. They can be used in a rehabilitation manner for arm and wrist injuries or to help with Golf, Baseball, Tennis, Hockey or Squash building arm strength and in such sports as climbing, rowing, mountain biking

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    Play.com (UK) : Powerball Original 250Hz Amber : Gadgets - Free Delivery
    Powerball Original 250Hz Pro - £14.99 Free Delivery .Play.com - Buy Powerball Original 250Hz Amber, with free delivery to UK and Europe