Lead with what body part?

i hear different body parts that the front side should lead with. I heard hip, glove, elbow and shoulder.

What would you tell your pitchers?

The initial weight-shift forward occurs at the hips and for high-momentum pitchers this should commence around the same moment as leg lift begins.

For guys like Dan Haren (and lots and lots of Japanese pitchers), who use a pronounced “stop at the top” to disrupt hitters’ timing, the weight-shift forward begins at the hips after the leg lift has reached its highest point.

Going into the stride, the glove side should swivel into place out in front.

The throwing-arm shoulder is the last body part to line up with the target–that doesn’t happen until after the ball is released and the pitcher is into follow-through.

Ditto what laflippin said. Lead with the front hip.

By the way, leading with the front shoulder is a mechanical flaw that leads to other problems including reduced velocity and more stress on the arm.

Same as above. Here are pics: