SMALL BALLS. BIG ARMS.
POWERBALL WORKS LIKE NO EXERCISE DEVICE YOU’VE EVER PICKED UP
From the tips of the fingers, into the hand, through the wrist joint, up along the forearm into the bicep and culminating in the shoulder, there isn't a single muscle or tendon in the arm that escapes the smooth but punishing inertial resistance generated by a fast spinning Powerball.
It's like a rapidly spinning vortex in your hand; the faster the engine spins, the more inertial resistance it generates, working your arm harder and harder until your muscles are burning and screaming for you to stop. And because it’s pure isometric resistance, Powerball engages almost the entire group of fibers in each muscle that it’s exercising, ensuring that you’ll reach fatigue in a much shorter time frame than with traditional exercise methods (in fact - less than 30 seconds if you really accelerate the Powerball’s rotor speed)
Put down your dumbbells and take a fresh look at the way you exercise - small balls really can build arms of steel.