Barbell Deadlift

Trains the Spinal Erectors.

How to do it

Load the bar and stand with your feet about hip-width apart, closer than a squat stance. The bar should sit over the middle of your foot and almost touch your shins.
Bend at the hips and reach down to grip the bar just outside your shins, so your arms hang straight down without pushing your knees apart.
Bend your knees until your shins touch the bar, but no further — the bar must not move forward. Your hips will end up somewhere between your knees and your shoulders, higher than a squat and lower than a standing bend.
Set your back before you pull. Lift your chest and pull your shoulder blades down, and take the slack out of the bar by pulling up against it until the plates just begin to shift. Your spine should hold one shape from here until the bar is back on the floor.
Take a breath into your stomach, brace hard, and squeeze your lats to hold the bar in tight against your legs.
Push the floor away with your legs and let the bar rise straight up your shins. It should stay in contact with your legs the whole way — a bar that drifts forward puts the load in front of your hips and makes your lower back carry it.
As the bar passes your knees, drive your hips forward to finish standing tall. Stop there: leaning back at the top adds nothing and loads the spine in the position it is least able to handle it.
Lower by pushing your hips back first, then bending your knees once the bar passes them. Reset your breath and your back position on the floor before the next repetition.

Letting the bar drift away from the legs. Every inch forward increases the leverage the weight has against your lower back. Keeping the lats engaged — think about squeezing an orange in each armpit — is what holds it close.
Rounding the upper back under a load too heavy to hold position against. The erector spinae work here is mostly isometric: their job is to keep the spine in one shape while the hips and knees do the lifting. When the shape changes, the load has exceeded what the position can be held against, and the answer is less weight rather than more effort.
Hips shooting up first, so the bar leaves the floor with the legs already straight. That turns a deadlift into a stiff-legged one and skips the leg drive entirely. Starting with the hips slightly lower and thinking about pushing the floor away rather than pulling the bar up fixes it.
Hyperextending at the top. Leaning back to prove lockout adds nothing to the lift and puts the lumbar spine in its least favourable position under a heavy load. Standing tall with the hips fully forward is the finish.