With out getting too crazy here, your making yourself lose your back tension as you get into the hole. Watch closely and your see that as you get into the hole you push up on the handles. This temporary keeps you more upright in the hole, however, when you go to stand up, unless you are do some where overheadpressesque movement to push the handles up as you stand up which is not recommended, you’ve totally lost your upper back tension and the bar knocks you over.
It make seem harder on the way down but you need to pull the handles in and lock your back in hard the whole time and you will tilt forward less.
