Buy In:10 reps Bridges, Side-lying bridges, toes to bar, ghd sit-ups, pvc good mornings.
Progressively warm up and then:
10 heavy singles@90+%. You have some options with this format. You can go straight sets (same weight) for all 10 reps or you can load progressively. Begin counting your singles once you hit 90%. If you allow your ego to drive you are asking for debilitating back pain. You can always spot the people who've never suffered an insult to their spinal health as their backs typically resemble the curvature of Katniss' bow as they lift the weight off of the floor. The folks who have had such severe back pain that they literally can't put on their socks are also easy to pick out. They usually have immaculate form.
tl/dr: don't be a dummy, use good form.