Serious inquiry- even as a trainer and experienced bodybuilder I don't lnow the technical lifts as well as some of the more proficient O guys. I try to get my clients to squat similiarly to the fellow in the first post. One- a 65 year female physician does pretty well, gets below parallel but back incline is more than I want. She learned from Rippetoes stuff before approaching me. She is fairly tall ~5'9" ish. Others can't get parallel even without feeling off balance. I have trouble myself doing it without a lot of forward bend - without weight even- so that isn't the issue I am addressing. One thing I have noted is those with shorter calves and relatively longer thighs seem to have an easier time going "ATG" whereas those with shorter thighs and longer calves have a hard time. The levers just are off. I can get down that far only by putting my feet way out in front on a Smith machine. I can do it on a V Squat too - but I have to fold like a pretzel to do it. No way I am doing that with serious weight on. My back wont like it. Anyone have a work around that works on free bar squats? (Been working on this for 25 years, so time and practice are not helpful solutions- neither is - "stretch"). Eric Bui told me as long as you hit parallel, that is all you need for bodybuilding. Mentzer said roughly the same- to parallel or slightly below. I know that the O lifters do much better in that respect- with a straight back, upright- which is the only way I will do heavy squats.
Several issues come to mind.
1. When a client comes to you, do you test for asymmetries? Some people are not ready to squat yet because they can't. Pelvic tilt, poor dorsi-flexion, poor thoracic mobility, tight hips, posterior chain, etc. We use the FMS (Functional Movement Screen) for EVERYONE.
2. Never teach a squat with a load (bar) on their back until they have perfected the squat first.
3. To help with mechanics, don't warm up on a bike or treadmill, rather use mobility drills instead (make them move, doesn't matter if it's the general public, elite athlete or a bodybuilder)
4. Squat progressions should start with an overhead squat. It's a good test for thoracic and shoulder mobility (snatch grip) and external rotation.
5. Started actual squat progressions for the first month or so with a goblet box squat. It's forces the client to keep chest up, heals down, transverse abdominus tight. Don't touch and go, sit completely down and come up straight. This is an easy progression.
6. After that, take the box away but still using the goblet squat.