Most of you reading this are wondering... "How can breathing benefit my mechanics?"
And there's the problem. Mechanics. Mechanics. Mechanics!
Most of you don't have a mechanical problem, you have a movement problem. And a big part of moving correctly requires you to breathe correctly. So, until you can prove that you can breathe properly, there's no point in going any further.
It's that important!
Focus on the quality of the movement, not the number of repetitions. 4 reps is a good guideline, but if you need to do more or less, do more or less. It's all about the quality, not the quantity.
How To Hinge
If your lower back is pressing forward (see images below), that is not the hinge. The spine needs to stay neutral, so if you are feeling it in your lower back, try flexing your glutes to pull your spine back to a neutral position.