Trains the core to resist extension — the job it actually does under a heavy bar.
How To
Set your elbows directly under your shoulders and your forearms parallel.
Extend your legs back with your feet at hip width and your toes tucked.
Squeeze your glutes and tuck your pelvis slightly so your lower back flattens.
Hold, breathing shallowly through your nose, until form breaks — then stop.
Watch Out
A high hip position turns it into a rest. Keep a straight line from head to heels.
Thirty hard seconds beats two soft minutes. Quality ends the set, not the clock.
You should be able to talk — if you cannot, you are bracing with your diaphragm.
Coaching
Add difficulty with a weight plate on your back rather than more time.
Reaching one arm forward at a time makes it substantially harder.
Use it as a warm-up primer before squats and deadlifts.
Swap It Out
Same job, different equipment or difficulty. Any of these can replace the movement above.
Core · Bodyweight
Chest · Bodyweight