Light body tempering
Back and hamstrings 
Hip flexor stretch
Belt squat

DL
-all singles
135
225
315
405
495
585
675
765
815

Leg press
4x10, 1x20

GHR
3x10

Band resisted KB swings
3x20

I've put a lot of time and effort and emphasis on fixing my sumo technique and it's paid off. The two biggest changes that lead to this pull- opening my hips up and reducing my anterior pelvic tilt to allow my glutes to finish the movement.

[youtube=http://www.youtube.com/watch?v=-bi85xnai3Y]