Captainfluffy

I'm down for any of these days. What gravity thing?

It's sad that people now-a-days are so out of shape that pacing while on the phone shows an improvement.

Well your guess is as good as mine with body weight squats! I do know that torso angle in combination with shin angle dictates if the movement is hip or quad dominant. Perpendicular shins(with relation to the floor) with bent torso means more hip dominant while knees more over toes with torso straight is more quad dominant.

tl;dr - Butt back first then almost immediately break(really they are so close that it could be simultaneously) in the knees as it should become one fluid motion. Your hips and shoulders should move at the same rate throughout the entire movement. Meaning your hips should not come up faster than your shoulders at any point. If your knees and hips break at roughly the same time then your back angle will never change provided it's a weight you can handle. I'm no personal trainer or certified anything. All I have is experience with my own squatting style. Yes start with your butt back but then you must break at the knee almost immediately otherwise you'll be in some modified good morning squat thing. I think referring to "back angle" leads to too much thought in the hole and that is never a good thing. Good squatting style as I've seen is basically hips and shoulders moving at the same time with the bar being inline with the middle of your feet. The position of the bar on your back will dictate how much forward lean you will need in order to not fall over. I have a longer torso so I have to keep the bar low on my delts otherwise the strain on my lower back becomes my weak link. Putting the bar farther down my back means I can keep more upright but also means I target my glutes/hamstrings more than my quads. In order to balance this out I do front barbell squats a few times a week. I do barbell back squat upwards of 5 times a week and have spent the last 5 months doing this exercise as my main lift. I truly believe that the only way to get good at this exercise is to simply do it more often. Throw in some goblet squats to grease the groove and you'll be a squatting machine in no time. I take a weird stance on recovery....in that I don't. I lift heavy every single day with no "rest days". My nutrition and sleep is more than adequate to repair my body for the next days session. THIS WILL NOT WORK FOR EVERYONE and I had to slowly move my way to this type of routine.

Newbie here. I'd be all for a meeting of the nerds. Whats this oly seminar? I've been trying to find a way to learn some oly lifts but will probably hurt myself if I tried to learn it on my own.

You shouldn't take anything I'm about to say as medical diagnosis. Definitely consult a doctor/PT and ask about what you should be doing. I've always had bad back problems. Scoliosis(not that bad and over time it semi corrected itself) and just really weak lower back. I've found the best thing to protect my back is to build my own internal "weight belt". What I mean by this is to really strengthen your core muscles. I did NOT accomplish this by doing body weight crunches/sit ups. You need to think outside the box and use ever increasing weight to really build a strong core(lats, abdominals and obliques). The core muscles really help brace your lower back against any sheering force that can be applied during squats and deadlifts. A really good anterior core workout for me is to do goblet squats and really focus on keeping an upright back. Not only does this work out your quads but it also forces you to keep your core super tight just to stay upright. As a byproduct you will most likely learn a thing or two about creating some intra abdominal pressure by expanding your stomach with air. Remember this works for me. Not sure if it will work for you but it should get you thinking about what you can do at least.