Medicine ball squat clean
Although the clean as a technical lift comes from the specialized sport of Olympic weightlifting, the mechanics of the move are applicable in everyday life. In essence, it is nothing more than the safe, effective way to lift a heavy object--here, a medicine ball*--from the ground to a supported position at the shoulders.
Standing above the medicine ball, the athlete squats into the setup position, arms straight, back and shoulders rigid and set. She squeezes the ball off the ground slowly, without bending the arms at all, and continuous, controlled momentum elevates it past the knees. The hip has yet to straighten. As the ball passes the knees, the hip and shoulders extend rapidly, accelerating the ball upward enough that, in the moment of hang time as it reaches its apex, the athlete can quickly pull herself under it into a full squat. From there, she completes the lift by rising immediately to a standing position.
The ball remains close to the body at all times, rising in a straight vertical line from the floor along the thighs and belly until it is just high enough for the athlete to get under it. Neither the ball nor the hands ever arc out in front of the body. In no way is the movement a biceps curl; in the photo sequence, note that the ball itself does not rotate at all. A person standing directly in front of the athlete, only a med-ball’s width away, would never get hit by the ball.
Done with some weight and/or for reps, it requires and develops an ability to generate power through coordinated, full-body core-to-extremity movement that is also essential for sport. (Not to mention significant cardiorespiratory capacity.)
*Issue 25 of the CrossFit Journal contains an article on the benefits and fine points of the medicine ball clean.
Arms straight, drive with the legs, finish the pull into the upper abdominals. On the recovery, hands pass over the knees before the knees break. Reach forward and go again. Some of the common faults are 
