The first time I saw commercials about PowerBall my first thought was:"What is so special about this to make such noise about it?" But after my dislocated elbow my oppinion about the use of it drastically changed, since I've bought it myself. I had a hard rechabilitation for almost a year and stil could't spread out my arm not saying that there was absolutely no power in my arm whatsoever. Tried to lift some wights but it was way to painful. So I thought:" What a heck, let's give it a try", since the basic thing I had to acomplished was to gain muscle power back in my arm. So, I got the PowerBall and I was astonished by the use of it.
The PowerBall is a product from the NASA space agency. Since there is no gravity in space shuttles other excerxise methods would be insoficient so they made this one. It works on the same principle as giroscope. While the yellow corpe rotates very fast arround its own center during the moovements of your wrisp along with the PowerBall, it creates very strong phisical forces and it gives you the same feeling as you would be lifting weights. Ther is a data that it can make up to 15000 rotates per minute. I've seen few guys made it over that but this takes some practice and focusing as well. I managed up ti 12000 turns per minute (arround 15kg), but when I started 4000 was my top result and it was also painful because of the injured elbow and offcourse my first contact with the thing. But eventualy you get into the rhytm and progres is very fast and efficient. Just for orientation - 15000 turnes per minute would be equal to 20 kg of weight in your hand! There is a display on the ball as well so you can control your progres and eficiency during the practice, but you can use it for competition between your frineds to find out who is the best even though this is not the primary function of the ball offcourse:) It is a different and efficient way of weightlifting but, offcourse, it is mostly used to strenghten your arms muscles. I would advise the use of it also to all of those who type a lot during the long period of using the computer since the wrisps sufer prety much during the long term typing. It worths to try.
It is great rechabilitation accesory and I'm saying this from my own exerience. I would advise it to everyone who suffered an injury on the arm and has to gain muscle power back to it in order to use arm properly again as offcourse to the others who woul like to add additional muscle power (I suggest a model with the giher turns/minute maximum range - you can get them from 250-350Hz range). You can get them in different models by this I mean different colors and different power that you can gain from it. Offcourse this depends on your taste. I bought the blue one and during the use of it it shines in a very butiful sky blue collour. You also get the instruction on how to use it for certain parts of arm muscles.
Bottom of all, I advise it to everyone. Just remember this. My scepticizem turned into huge enthusiasm by using it.