The two most common things ooure either tucked here, your flat back, or yu over arched. 70 % of people that've seen me present in that position oversaid. This is from likely missing a developmental period in their life. They likely missed an athletic developmental period where they learned the hip hinge. The glots are extremely strong muscles. And the gluts and hampstrings return your body upright. That dead lift didn't cause that person to be half over developed muscles. We're hpinging improperly.