Coaching, according to expert lifting coach Mark Rippetoe, is no more than figuring out what to say to people to get them to move how you want them to move. This will vary from person to person, so, as a trainer, your bag of tricks--your ways of explaining and cueing movement and mechanics--must be broad and diverse. But, before that, you need to understand exactly what's going on in the mechanics of lifting and the body positions it requires.
This video continues Rip's discussion of lifting mechanics from last month's CrossFit Journal. Taken together, the two videos offer a clear, down-to-earth explanation of how and why the principles of force, physics, and human physiology determine the positions that constitute good--safe, effective, and efficient--form for the barbell lifts.