Every cue about keeping your chest up in the squat is downstream of something quieter: the brace. A torso is a column only when it's pressurized — big breath into the belly and sides, trunk muscles locked around it, a cylinder of pressure that holds one shape while your legs do the lifting. Without that pressure, "chest up" is a wish. The load finds the soft column, the column folds, and the fold gets blamed on everything except the thing that actually leaked.
What bracing actually is
Not sucking in. Not pushing your belly out for its own sake. The brace is a 360-degree breath plus tension: inhale down into your belly, back, and sides — imagine inflating a ring around your waist, not lifting your chest — then tighten the trunk around that pressure like you're about to be poked hard in the stomach. Held well, it makes your midsection feel less like a stack of parts and more like one piece.
The rhythm for squats: breathe and brace at the top, hold through the descent and the drive, exhale at the top when the rep is done. One rep, one breath, at any load heavy enough to matter. Re-bracing between reps — rather than coasting on a stale, fading breath — is half the difference between a set that holds shape and a set that dissolves.
How a leaking brace shows up on video
You can't film pressure. A camera — and honestly, any body-tracking system — cannot see inside your trunk, and CoachVision doesn't pretend otherwise. What it measures is the brace's job performance: whether your torso held one shape when the load asked hard questions.
The sharpest tell is the app's torso-hold read — how much your trunk angle changes from the bottom into the early drive. A braced column reads near zero: chest and hips rise together, the angle you set is the angle you keep. A leaking brace reads positive: the chest dips first out of the hole, the column bending exactly when the demand peaks. If that number flags at your working weight but stays quiet on lighter sets, you've localized the leak precisely — the pattern is fine, the pressure isn't scaling with the load.
Which points to an honest, slightly unpopular fix: train the brace lighter until it holds, then load it. A brace is a skill with a strength curve like everything else. Working weights that outrun it don't toughen it — they just teach your spine to squat unpressurized.
The drill — Dead-Bug Bracing
The brace is built on the floor, where you can feel every leak. Lie on your back, arms at the ceiling, knees over hips. Take the 360-degree breath, brace like the poke is coming — then slowly lower your opposite arm and leg toward the floor without your lower back arching away from it. Return, switch sides. 3 sets of 8 each side.
The rule of the drill: the moment your low back peels up, the brace lost. Move slower, shorten the range, win the fight, then earn the range back. What you're training is exactly the squat's demand — a trunk that holds one shape while limbs create chaos around it.
Run the dead-bugs three times a week, re-brace every rep in your squat sets, and film a side-on set weekly. Watch the torso-hold number sit down near zero and stay there as the weights climb. That's the sound — the silence, really — of a column that doesn't leak.