From Surf City Volleyball Director and Former UC Santa Cruz Men's Volleyball Coach, Mark Mattern:
Lets think about arm swing technique.
Since you probably want a fast arm swing and you want your arm, shoulder and rotator cuff to last a lifetime. The solution is technique, technique... SWING FAST! Think about the following steps to a fast, safe arm swing:
* To begin your swing, both arms should be swung up and in front of your non-hitting shoulder.
* Your non-hitting (opposite) shoulder and foot/leg should be forward, hitting shoulder back. (like a pitcher on the mound)
* Draw your hitting elbow back, as if it is attached with a bungee to the wall behind you. Palm facing away from your cheek.
* At no point in time, while drawing your elbow back, should your hitting hand be higher than your elbow. The elbow should be drawn back at shoulder level.
* Now your elbow is back and it's time to build up arm speed to impart into the ball.
* The large muscles of your lower body, quads, hips and pelvis begin the rotating forward motion of your hitting side.
* This rotating motion continues up your body, as the abdomen, chest and then hitting shoulder begin their orderly rotation forward.
* Once the hitting shoulder is in its forward motion, the arm needs to begin it's movement to the ball.
* The elbow must be the first part of the arm to start forward, it was pulled back first and it leads the way forward. The forearm and hand will come last, in that order.
* The elbow should come through high, with the forearm and hand following. Typically the arm will be fully extended at the point of contact with the ball. Think of your arm and hand as a whip.
* The hand is big, shaped like the ball, fingers wide. Although the entire hand will attack the ball, the power part of your hand is the top of your palm. The ball will go where your palm is facing.
*Muscle / brain memory can ensure that your arm swing is correct, but for this to happen, you must have practiced it perfectly many times.
* Slow down, do it properly and it can become automatic, giving you the ability to put pace on the ball and relieving some of the stress to your shoulder.
