To perform a good morning begin by placing the bar on your back in about the same position as you would a squat. The first thing to move during a good morning should be your hips. With a very slight bend in your knees, push your hips back and begin the descent. You should maintain a good arch in your lower back and keep your head up. Continue until your low back is about parallel to the floor and raise back up. You can use a wide, medium or close stance when doing a good morning.
The movement begins as a front squat and follows through to a push press/shove that sends the ball up and
forward to the target from which it rebounds back to the throwers outstretched arms where it is “absorbed”
back into the squat. In its entirety the wall-ball is quite simply a throw.
Crossfit guidelines use a 20-pound Dynamax Medicine Ball and a flat vertical target (originally the wall and hence the name) located about 8-10 feet above the ground.
The lift starts much like the deadlift, but with a wider stance and narrow grip. The weight is accelerated using your legs and hips to drive it to a top position directly under your chin. This movement is fast and moves the weight a long distance, therefore making the power output very high.
Requirements for the Sumo Deadlift High Pull: The bar starts resting on the ground and ends under your chin with elbows high.
Note here that he mentions “heels shoulder width apart”. It’s wider than you think
Mark Rippetoe, who is a great weight lifting coach, talks about proper squat form, and transitions it to how it applies under load with the bar on your back. His instructions are pretty simple, and he points out where the movement happens.