it's a posture thing....my pelvis is tilted a bit downward, so to fix it...have you strengthen the transverse abdominous....stretch hip flexors and quads, strengthen ass and hamstrings.

that exercise has me lay on my back on the floor....with knees bent at ninety degrees. at this point my back is still arched...so i flatten it...extend one leg out so it's either flat on the floor or hovering just above. and i hold it there while keeping my lower back flat on the floor. it is tough

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