Powerball - Training for Lower Arm

Accelerate the rotor while trying to hold the wrist firm and stiff. Now the power will automatically come from the muscles of your lower arm. You will even see how the muscles work and move.
Powerball is the best training device to improve the coordination of the lower arm muscles.
It is good warm-up before you start your sport. Even after only a short time of exercising you will feel your arm getting warm.
Regular Powerball training will prevent tennis elbow.