Part of my Lower Body Mobility series. Parts one and two cover ankles and hips.

This is the short part. Ankles and hips are where my range is missing. But even once they move, the squat only works if the torso stays upright and rigid. Otherwise the body steals the missing range from the lower back, which is the one place it should not come from.

Two things cover it: an upper back that can extend, and a trunk that can brace.

Upper back

If the upper back rounds under load, the chest drops, the weight drifts forward, and you fold. A quick test: lie face down, arms overhead, lift the chest and arms off the floor. If that is hard or the lower back does all the work, the thoracic spine is stiff.

Foam roller extension

Roller across the mid back, just below the shoulder blades. Hands behind the head, hips stay on the floor. Extend back over the roller, slowly, 8 reps. Move the roller up a few centimetres and repeat.

Open-book rotation

Lie on your side, knees bent at 90 degrees, arms straight out in front. Lift the top arm and rotate it open toward the floor behind you, following it with your eyes. The knees stay stacked. 8 slow reps per side.

Bracing

The brace is simple to describe and takes practice to do under load. Breathe in, tense the belly as if about to be punched, and keep that tension through the whole rep. These three moves teach the pattern without any weight.

Dead bug

On your back, arms up, hips and knees at 90 degrees. Lower the opposite arm and leg together, slowly, stopping before the lower back lifts off the floor. 8 per side.

Bird dog and the McGill big three

Hands and knees. Reach one arm and the opposite leg out until they are level with the torso, hips square, no sag. Hold a second, come back, 8 per side. This video covers it along with the curl-up and side plank, which make up the standard back-friendly core set from Stuart McGill:

Glute bridge

On your back, knees bent, feet flat. Drive through the heels, squeeze the glutes, lift the hips until shoulders, hips and knees are in a line. Do not arch past that. 12 slow reps. This wakes the glutes up so they do the work in the squat rather than the lower back.

Where it fits

Five minutes, after the ankle and hip work and before squatting. The full sequence is on the main page.