According to my doctor I had a minor strain in my back after I did 405x5x5 (sumo), so I'm trying to clean up my form to avoid doing so again.
I warmed up with 225x5, 315x5 and proceeded to the following:
Set 1 (Conventional): 405x2 http://www.youtube.com/watch?v=vkntDvJ5tZU
Set 2 (Conventional): 405x1 http://www.youtube.com/watch?v=KrcHQvm6mw4
Set 3 (Sumo): 405x1 http://www.youtube.com/watch?v=KHIvRhfqG1k
I was trying to really focus on leaning back into it, but you can see it still looks like I'm drifting forward over the bar. Any advice on my weaknesses (and how to fix them) would be appreciated.