The beefy rig is a body mechanics rig designed and rigged by Ugur Uri Yeltskin for maya, and translated by me to blender, its simplicity, flexibility and appeal will be perfect for you to practice your body mechanics character animation skills.

it features:

Swiches to turn on an on different parts of the body so you can concentrate in one thing at a time.

And a picker for selecting your controls with ease.

And also the standard rigify features like IK FK snapping, sculpt bones in arms legs and torso, and more!