If you look at the picture below you see a youngster going through a 'great looking' gym squat that encompasses the 'rules' of training to serve and protect the low back.
From: Sir. Paul Edmondson
There are many points listed in the picture which we could discuss 'is it the ONLY way?', but in the interest of just a 'quick hit' on Low Back Health, we will focus on the 'Upright Torso' point (top right of picture).
Whilst this approach many agree on is the ideal way to distribute stress through the spine evenly and protect the discs from undue strain and maintain segmental stability?..
Thinking slightly out of the box, a Squat utilising a 'Flexion' response at the Spine (as in squatting down and picking something off the floor as a visualisation of this 'tweak') MAY in fact contribute BETTER to Low Back health.
Here's why...when you 'flex' the spine the bones relatively de-compress (tension moment) the discs (interestingly replenishing fluid through movement hydration) and it 'lengthens' the big white connective tissue structure in the small of the back termed 'Thoracolumbar Fascia'. When a tissue (particularly fascia) lengthens it 'turns it on' meaning it activates proprioceptors (fascia 10 times more proprioveptively rich than muscles) that communicate the tissue to the rest of the body to enable to spread forces globally throughout the body as opposed to localising stress in one area (all too often the low back), because of the Thoracolumbar fascias connection to ALL 4 limbs it is the perfect stress/strain distributor (and because it sits more superficially under the skin, it's location to the spine is further away from the muscles like TVA, Rectus abdominis and erector spine at the back- etc that sit close to the spine, meaning the further away from the axis of rotation the stronger its influence to the Torque at the spine- think of a wrench and how you tighten a 'nut' holding further away from the nut at top of wrench) so if I utilise this fascial approach to squatting as opposed to the more muscular 'gym style' squat the more efficient and effective the outcome for strength and stability.
Now be careful I'm NOT suggesting this approach to back loaded squats in a gym! No way, but (bodyweight the spine would rather use this approach given the choice) as a means to off set, prevent or even rehab low back pain this COULD be a great solution!
Remember there's many more ways than one way to squat, and everyone's squat requires individualising based on what Is desired by the recipient.
Give it a try........
Source: Gray Institute