Deadlifts and the lower back

[Cancer Merchant]

Hi All,

I'm a lifting beginner, just started the Rippetoe routine listed in the FAQ at my local gym. This is week 3, and I've been seeing quick improvement in my squat and DL numbers (120 and 195, respectively), and slow improvement in my bench (stalled at 65).

This morning was squat/DL/bench day. I started with squats, then progressed to the DL using the same weight as my Monday routine (195), planning on increasing after my first 5 reps. My lower back has been bothering me from the small of the back to just under the ribs. When I tried to lift, I started with my legs and hips, but as soon as I engaged my back my lower back gave out. I lower the weight by 20 pounds and could make out three reps before the pain was too much. I threw in the towel and moved to the bench (and made up the lack of lifts by ending with 3x5 power cleans @75lbs ...cleans are fun!)

My question is, should I be engaging my lower back in the DL? Or should it be all in the hips and the shoulders? Is there a specific problem in my form that this could indicate?

As an aside, I think my back problems come from a problem with my squat form. With heavier weights I would rock forward in the hole and start to come up on my toes. This led to me rounding my back and having to unround it to finish the squat, putting strain on the shoulders/back instead of my legs. Looking up when I squat and putting the bar farther down my shoulders instead of on top of the traps has partially fixed this, but I still tend to rock forward when putting more weight on the bar.

I'll have to borrow a digital camera and tape my motions. Thanks!