Move a barbell from the back of your shoulders to the front of them and you've technically changed one variable. Functionally, you've changed the sport. The front squat and back squat share a bottom position, a depth standard, and a set of legs — and disagree about nearly everything the torso does. Understanding the disagreement is how you pick the right tool, and how you stop grading one lift by the other's rules.
What the bar's address changes
Torso angle, first and loudest. A bar racked on the front of the shoulders sits forward of the spine already — lean appreciably and it rolls off. So the front squat lives nearly vertical at the bottom, elbows up, chest proud, by mechanical necessity. A back squat carries the bar behind the neckline, which permits — and at low-bar placement, requires — real forward lean to keep the load over mid-foot. Neither angle is a virtue or a vice. Each is the geometry doing its job.
Who fails first. Front squats are famously honest: the moment your upper back softens or your trunk stops fighting, the bar dumps forward and the set ends — you rarely grind an ugly front squat, because ugly isn't structurally available. Back squats are more forgiving, which is their gift and their trap: they let you finish reps through positions a front squat would have vetoed, including some worth vetoing.
What gets trained hardest. The upright front-squat torso bias loads the quads and upper back ferociously. The back squat's freer geometry lets total load run higher and shares more work with hips and posterior chain. Strength generalists want both in the rotation; most people just want them in the right order — and the front squat's honesty makes it a superb teacher early on.
What doesn't change
The floor under all of it is identical. Depth is depth — hip crease and knee don't care where the bar sits. Knees track over toes in both. The descent is controlled in both. Hips and shoulders leave the bottom together in both — a front squat that good-mornings simply drops the bar, while a back squat that good-mornings quietly taxes your back, which is precisely why the pattern needs watching in the version that lets you get away with it.
This is where filming earns its keep. Tell CoachVision which barbell squat you're doing — back or front — because the tracker reads your body, not the bar, and the load context calibrates what a sound torso angle at the bottom means: a front squat's measured lean should live down near vertical, while a substantial back-squat lean can be the style working. Everything else gets read on the shared standard — depth, knee bend, hip-shoulder sync, the balance line, tempo — because those rules never moved. One clip per variant, side-on, and you'll see exactly what each version of your squat does differently, in numbers instead of impressions.
The drill — Wall-Facing Squats
The front squat's demand — a vertical torso through the full rep — is trainable without a bar. Squat facing a wall, toes a few inches out, 2 sets of 8 bodyweight: the wall forbids the forward tip, and your body learns the tall channel both lifts reward and the front squat requires.
If you only run one, run the one that fits your goal: front for quads, posture, and honesty; back for total load and posterior chain. But film whichever you run, label it honestly, and let the measurements referee. Same legs, different torso — now you know which torso you're training.